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New Dwelling at Gormack Cottage
Final Document
By: Jonathan Watson
To be submitted by 8:45 am
on Thursday 1st
May 2014.
HNC Construction
Graded Unit
HNC Construction: Graded Unit
Contents
1.0 Summary
1.1 Clients P3
1.2 Project Aim P3
1.3 Clients Needs P3
1.4 The Site/Existing Building P3,4
2.0 Planning Policy
2.1 Scottish Planning Policy P5
2.2 Associated Policy P5,6
2.3 Conclusion P7
3.0 Construction Industry Report
3.1 Introduction P8
3.2 Local Authority Planning Department P8
3.3 Local Authority Building Control P9
3.4 Method of Procurement P10
3.5 Involvement of Construction Professionals P10,11
3.6 Conclusion P11
4.0 Solution
4.1 Summary P12
4.2 Site Layout P12
4.3 Floor Layout P13,14
4.4 Form P14,15
5.0 Domestic Construction Methods
5.1 Introduction P16
5.2 Substructure P16
5.3 Superstructure P16,17,18
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6.0 Building Services
6.1 Heating P19
6.2 Electricity P19
6.3 Water and Drainage P19
7.0 Material Specification
7.1 Introduction P20
7.2 Specification P20,21,22
7.3 Dimension Paper P23
7.4 Rates P24,25
7.5 Bill of Quantities P26
7.6 Heat Loss Calculations P27
8.0 Health and Safety P28
9.0 Setting Out
9.1 Introduction P29
9.2 Equipment P29, 30
9.3 Accuracy P30
9.4 Method P30,31,32
9.5 Conclusion P32
10.0 References P33,34,35
HNC Construction: Graded Unit
1.0 Summary
1.1 Clients
Jack and Brenda Forbes are a retired couple who are looking to either extend on existing
home or develop a new property on the same rural site that lies between the small towns of
Peterculter and Drumoak, west of Aberdeen. The new or extended dwelling will serve as a
home for newly made redundant, wheelchair bound son Robert and his wife and young
children.
1.2 Project Aim
The client wishes to provide a comfortable, modern and accessible home for Robert Forbes
and his family. There should be three bedrooms (two of ‘twin’ size and one of single), a
shared bathroom with shower cubicle and WC as well as a separate WC and basin. En-suite is
not essential. Sitting room, kitchen and dining room/area are to be included. The build
should be stylish and modern, without unreasonably raising the cost. The surroundings are
lovely and the family wants to be able to appreciate them. Privacy between the two dwellings
should be a priority. Project may be a separate building or it could be an extension to the
existing property. The client can raise sufficient capital to carry out the project however,
there should be no ‘unnecessary’ extravagance.
1.3 Client Needs
Robert’s handicap is to be a fundamental element of the design. The wheelchair accessible
dwelling will cater the client’s needs and allow for the family to happily occupy.
1.4 The Site/Existing Building
The site is considered to be part of a flood plain and is considered green belt. Access is from
Gormak Burn Road on the south side of the Site. The Malcolm Burn bounds the east side of
the site and an un-named stream lay on the western boundary. This stream has, at some
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point in the past, been diverted and drained leaving the area immediately around, and to the
north of, the exiting house relatively dry. The water from the drain is pumped into Malcolm
Burn. Majority of 1500m² site in un-useable due to high water table. The plot is fairly level
around the existing house and immediately behind it but slopes up on all sides beyond this. It
is surrounded by manmade embankments, approximately 1.3 to 2.0 metres high. These assist
when water levels rise however additional flood prevention measures may need to be
considered. The soil, being waterlogged most of the time, has uncertain to poor load-bearing
capacity. The added drainage around the existing house however has significantly helped the
situation. It has not suffered flooding in twenty years but may be susceptible to a 1 in 100
year rainfall.
The existing house is detached with access to all sides of the house. The walls are built of a
mixture of local stone and rendered blockwork and the roof is of natural slate. The 25 year
old dwelling of traditional construction, may allow for the future development if appropriate.
Water tanks are stored in loft and heating is by a pressure jet oil burner located in the pantry
(floor standing with a flue from back directly to outside). An oil storage tank, screened by a
shed, is located in the garden north of the parking area to the west side of the house. Access
must be maintained for refilling. Mains gas is not an option. Drainage is via sewer pipe in the
road leading to three large septic tanks, recently replaced and located in the front garden
area. These are more than sufficient for the existing building. Existing road provides access
for emptying. Rainwater from the roof is picked up by drainage system. Mains water and
electricity are both available. Timber fuel is stored in sheds in the garden.
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2.0 Planning Policy
2.1 Scottish Planning Policy
The purpose of planning is to guide future development and ensure that the land use is
optimised for the benefit of the community. For sustainable economic growth to occur, the
Scottish Government believes that a properly functioning planning system is vital and
introduced Scottish Planning Policy (SPP) in 2010. This is a statement on land use and
planning and contains the Scottish Government’s view on the purpose of the planning system,
fundamental values of the operation of the planning system, concise subject planning policies
and the expectations of the intended outcomes.
2.2 Associated Policy
Principle areas of the brief need to be studied in conjunction with SPP to ensure that the new
extension/dwelling is in accordance and will be supported by the government and local
authority (Aberdeen City Council).
The policy states that its function is to ‘enable the development of well designed, energy
efficient, good quality housing in sustainable locations’. By ensuring that the proposed design
abides by the listed criteria, the Aberdeen City Council planning department that bases its
reasoning around SPP will be more likely to grant planning permission.
Policy with regard to rural development, states that ‘opportunities to replace rundown
housing and steadings, and to provide limited new housing along with converted rehabilitated
buildings, should be supported where the new development is designed to fit in the landscape
setting’. Having studied the brief, it is clear that the aims set by the client are in accordance
and are again strengthened as the policy continues with ‘modern and steading conversion
should not be constrained within the original footprint or height limit unless there are
compelling design or conservation reasons for doing so’.
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Green belt planning policy states that its purpose is to ‘direct planned growth to the most
appropriate locations and support regeneration’, ‘protect and enhance the quality, character,
landscape setting and identity of towns and cities’ and ‘protect and give access to open space
within and around towns and cities’. Based on the fact that the policy is aimed at areas that
could be harmed by unplanned growth and that the site is in a rural location on the outskirts
of Aberdeen, local authority are more likely to approve the development at this green belt
location.
A concern with the project is that it could risk flooding in the event of a significant rainfall.
The Flood Risk Management (Scotland) Act 2009 was introduced to deliver a sustainable and
risk-based approach to managing flooding. This is outlined in SPP, which aimed to have flood
risk management plans in place throughout Scotland by 2015, which should be taken into
account when development plans are prepared. The act places a duty on Scottish Ministers,
SEPA, local authorities, Scottish Water and other responsible authorities to begin managing
and reducing flood risk and promote sustainable flood risk management. We already know
that the site has the potential to flood due to watercourse surrounding site and this is
illustrated on the SEPA National Flood Risk Assessment map as a potentially vulnerable area.
The summary of main impacts of the flood risk assessment carried out in the area states
‘assessment of future flood risk and past events shows that Culter Burn/Gormack Burn
presents: potential impact to some residential properties, with past reports of flooding in the
area’. The assessment also shows that 66% of the source of flooding will be from rivers and
34% will be from surface water.
Having confirmed that the site is in fact at risk of flooding and acknowledging the policy
‘development which would have a significant probability of being affected by flooding or
would increase the probability of flooding elsewhere should not be permitted’, it may prove
challenging to get this project planning permission. However, additional flood defences can
be incorporated into the design and the finished floor level of the house can be raised, in
order to swing local authority planning officers in favour of the development.
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2.3 Conclusion
Therefore having reviewed the brief alongside the SPP, two conclusions can be made. In
terms of developing in a rural environment and on a green belt location, this development
complies and would be granted planning permission. However due to risk of flooding, an
innovative, sustainable design is required to allow for the development to become realised.
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3.0 Construction Industry Report
3.1 Introduction
The client wants to know the roles and relevance of the Planning and Building Control
departments of the Local Authority and at which stage they are likely to be involved in a
building project. They are also curious about which construction professionals will deal with
them and why/in what capacity. In order to give the client an accurate impression of this, the
method of procurement for the project must first be identified by evaluating the client’s
objectives and priorities.
3.2 Local Authority Planning Department
As previously stated under planning policy, the purpose of SPP is to guide development and
encourage sustainable growth at a national level. However the local authority (Aberdeen City
Council) that will be responsible for the proposed project has used SPP as guidance to create
local policy, which is set out through the Aberdeen City and Shire Structure plan and
Aberdeen Local Development Plan. This encourages both the public and developers to work
together in order to promote the Scottish Governments primary aim of sustainable economic
development. This ensures that land is used in the best way for the long term interest of
everyone. Section 2.5 of the development plan introduced on 29th
February 2012 states ‘New
development, whether in greenfield or brownfield locations, will have to be of the best
standard to deliver opportunities for people to enjoy a high quality of life within an attractive,
sustainable and safe environment’. This policy among others is controlled and regulated by
the process of applying for planning permission.
It is at this stage at which a local planning officer will review the application and make a
decision to grant approval or not. Either a householders application will be submitted if the
development is to progress as an extension, or a non-householder application in the case of a
new house. If a non-householders application is submitted, the local authority planning
officer will need to review plans of proposed building (including location plan, elevations,
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cross sections showing existing and proposed levels, site level and landscape plan),
environmental statements (Environmental Impact Assessment), water and drainage design
and flood risk assessment before coming to a decision. The development manager at the
council can assist with any pre-application queries.
3.3 Local Authority Building Control
Local authority building control departments of the local authority differ from planning
departments, in that they are focused on providing and enforcing building regulations to
ensure the safety and health for people who will occupy the buildings. These regulations set
out in the Building (Scotland) Act 2003, set standards for the design and construction of
buildings. They also ensure that fuel and power is used efficiently and that facilities are
provided to meet the needs of people, including those with disabilities, who require easy
access and room for mobility.
Aberdeen City Council requires a single set of coloured plans from the applicant in order for
officers to grant consent to building warrant. To enforce that the design of new buildings
abide by building standards, the local authority fulfils two roles, as stated on the council
website. The first is to act ‘as verifier to protect the public interest where applications for
building warrant to construct, alter, extend, convert, provide services, fittings or equipment
to buildings or demolish buildings have been or are about to be made’ and secondly ‘to
enforce building legislation in respect of building work carried out without approval and to
ensure public safety in respect of dangerous and defective buildings through enforcement
processes’.
The Health and Safety Executive (HSE) may also need to be notified when construction or
building work is carried out and other duties under the Construction (Design and
Management) Regulations 2007 (CDM 2007) may exist. The domestic client will not have any
of these duties under CDM 2007, although those employed to carry out the construction of
the project will.
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3.4 Method of Procurement
According to The Joint Contracts Tribunal (JCT) procurement is described as ‘the activities
undertaken by a client or employer who is seeking to bring about the construction or
refurbishment of a building’. It is important that the client’s aims are considered when
selecting the method in order to increase the chances of success. As the client has wished for
the designers and contractors to be appointed separately, it is recommended that the
traditional method of procurement is chosen. This is a tried and tested approach that is
design led, which will allow for changes to contract to be arranged and managed easily and is
appropriate for the project as an exact timescale has not been given and may allow for
sufficient time. Those involved throughout the project can be held accountable due to a
competitive selection of tendering contractors. This method will ensure that an attractive,
high quality home is developed that will sit pleasantly with its surroundings and please the
client.
3.5 Involvement of Construction Professionals
Having recommended a method of procurement, information regarding which construction
professionals will deal with the client and why/in what capacity can be given. Firstly,
throughout the design stage the client will mainly deal with the chosen architect who will
prepare drawings and specifications, obtain planning permission, prepare legal documents,
plan construction process, advise on the selection and communicate with the construction
team and inspect work. The degree of involvement will be significant as meetings and
negotiations between the client and architect will be carried out to ensure the clients aims
are realised and represented throughout the process. The client will have little involvement
with the rest of the design team, including the structural engineer and quantity surveyor and
will rely on the architect to lead.
During the construction stage of the project, the clients will have to deal with contractors on
site to some capacity if they intend to occupy the existing home. Important issues however
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will be dealt with the architect, who will be overseeing the entire process on behalf of the
client.
3.6 Conclusion
Therefore the roles and relevance of the planning and building control departments of the
local authority and the stage at which they are likely to be involved in a building project have
been described for the client. A suitable method of procurement (traditional) has been
recommended and the construction professionals associated with this listed, including the
capacity in which they will be involved with client and why.
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4.0 Solution
4.1 Summary
From the offset it was clear that the optimised solution would take the form of a separate
home, as privacy between the two families was to be made a priority. It would have proven
to be too challenging as an extension because of the existing buildings current floor
arrangement/orientation on site, site topography, current field drainage and the client’s
access needs, without blowing the budget extravagantly. To arrive at the best solution
quickly and successfully, an engineered approach was taken as opposed to making trial and
error sketches. This was done by incorporating current building regulations related to the
client’s specific needs from the start. This led to the form of the design being largely
influenced by its function. Sustainability and client convenience were kept as the main focus
throughout the process to make sure the end product would please both local authority
planning departments and primarily represent the client’s aims and needs.
4.2 Site Location
The new build is to be located directly behind the existing property, where the stream, at
some point in the past, had been diverted and drained leaving the area relatively dry. Due to
the water table however, the site may need to be temporarily dewatered during construction
stage and permanently drained after. This area is fairly level so minimal fill would be
required to provide a proposed ground level of 40.400m immediately around the
development. Steady fall of the land to the north will allow for an open garden area for the
family to use. A path from the top of the embankment from the south-west will link to
entrance ramp, external storage area and through to the north of the site. The building will
not disturb existing site drainage and is far enough from existing property to comply with fire
regulations and maintain privacy. The building will be positioned with the same alignment as
the existing property.
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4.3 Floor Layout
The floor layout has been designed to comply with Aberdeen City Council’s ‘Improving Access
to Buildings and Services’ document. The entrance ramp has been designed at a 1:15 rise
from the path (40.400m) to the landing at a 4.5m going, which will share a 40.700m level with
the finished floor level (FFL). An area to the rear of the property, which has been design to
allow for rear access and a WC for family members excluding Robert Forbes, uses the only
corridor that is not in accordance with the minimum 1.2m wide lobby and 300mm from wall
to opening side jamb regulations. This is also true for the 1.5m diameter turning circle that is
required in a room for wheelchair users. The entrance hall provides a large open space which
allows convenient access to all rooms.
One single and two twin bedrooms make up the southern area of the proposed development.
This decision was made to allow for living and kitchen areas to be located to the rear of the
building and provide privacy from the rear existing garden. This allows each bedroom to get
morning/midday light with windows facing to the east and south. All main rooms will provide
a 1.5m turning circle and minimum 900mm openings to allow Robert to access the majority of
the property, leaving him unrestricted to provide for the needs of his family. Each bedroom
will include built in wardrobes.
The shared bathroom will comply with the ACC document but has been primarily influenced
by the Portsmouth City Council ‘Design Guide for Wheelchair Accessible Housing’. The
foundations of this guide are based on Part M – Access to use of Buildings of the NHBC
Building Regulations, which sets out the Disability Discrimination Act 2005 & Building
Regulations 2000. This has provided more in depth information including dimensions of
fittings, to better suit the client’s needs. The bathroom will include pressed steel bath (min
1700mm x 700mm x 500mm high) with bath board, railing and shower controls and
appropriate toilet and sink. A frosted window will look onto external sheltered storage area.
The sitting room / living area has been designed to utilize surrounding beauty of the area by
incorporating large glazing at the gable end to the east of the site and a glazing at the
northern and southern walls. Morning and some afternoon sun will provide an enjoyable
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degree of natural light. The ceiling will follow the same pitch as the roof, which will be
supported by a portal frame. This will create a virtuous living space that the family will enjoy
relaxing and spending time in privately, as it does not look on to the existing property. Half of
the room will be unglazed to provide the family with some wall area for bookcases/mounted
wall televisions etc.
The kitchen and dining area have been combined to maximize use of space and increase
convenience for the family, due to Robert’s needs. Similarly to the shared bathroom, the
layout of the kitchen was influenced by the Portsmouth City Council ‘Design Guide for
Wheelchair Accessible Housing’, to enable Robert to provide for himself and his family with as
little restrictions and as much convenience as possible. This includes a 1.5m turning circle
between the kitchen units. There is sufficient room for a large dining room table and a small
window above the sink will provide natural morning light. A large sliding door gives access to
the rear timber decking and external wooden pellet boiler store, which will allow for the
family to change the boiler without difficulty when needed. It will also provide natural
sunlight in the afternoon and an area for Robert to relax outside, without having to travel
from one level to another.
As discussed, the WC and rear access door of the property have been incorporated for the
ease of other family members. An example of this is the children using the WC to clean up
after playing outside in the rear garden to prevent mess being carried throughout the house.
The corridor will also serve as a barrier between WC and the kitchen to prevent unpleasant
odors. An external storage area will also be found behind the pellet and boiler and single
bedroom, sheltered by the equal span of duo pitch trusses supported by the timber post.
4.4 Form
The building will comprise of a fine textured render finish on blockwork, with a course of
natural sandstone to the base. By including modern glazing and large fascia boards, this
construction will allow the development to sit in harmony with the existing stone/render
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property, while providing a fresh, sustainable home for the family to enjoy. Natural slate will
be the sustainable material of choice for the roof finish.
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5.0 Domestic Construction Methods
5.1 Introduction
Having reviewed the client’s needs and aims and the characteristics of the site and existing
building, a recommendation can be made on the methods of construction that should be used
to ensure the success of the development.
5.2 Substructure
Deep strip foundations will be used to transmit the loads of the building into the soil beneath
ground level. These are required because of the low load bearing capacity of the top soil and
therefore the foundations need to be poured to deeper soil with better bearing capacity.
Existing borehole information is not freely available in the area from the British Geological
Survey, so it is recommended that the client employs a geological engineering consultancy to
analyse the soil properties. For the purposes of the project however an assumed level of
sufficient load bearing capacity soil will be given 2.0m below existing ground level (38.000m).
5.3 Superstructure
An appropriate construction method for the structure of the building must be recommended
because each of the types will have a different impact on lead into construction and on site
labour timescales and will bring a variety of advantages and disadvantages that will influence
the success in terms of practicality and costs. Having considered the above it is
recommended that the house will comprise of a timber kit structure, which should be
seriously considered when the ground you are building on is particularly poor and you wish to
promote the use of environmentally friendly materials in a timber friendly area such as
Scotland.
Using timber kit construction will allow for quick on site erection and will significantly reduce
site labour. Although this requires a longer run in to construction time period for the design
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and manufacture of the timber frame (estimated at 8 weeks) compared to the short
preparation for a masonry build (2 weeks), it would only require an estimated 7-10 days for
the erection period compared to the 6-8 week traditional on site period. This would benefit
the client as they will most likely occupy the existing building throughout the programme and
will be able to reduce the volume of disturbance from on site labour. This speed will also
prevent any delays to the programme from other trades including electricians and plasterers
who rely on the structure to be weather tight to progress.
Another clear advantage is the thermal performance of timber frame construction, which
contains its insulation within the depth of the walls. By designing and constructing to current
building standards, high energy efficiency can be obtained and can prevent moist air reaching
the inside of the building by using a vapour control layer. The low thermal mass of the kit
also allows for quick heating of the home, which will benefit the clients as they are likely to
find equal employment opportunities in the city of Aberdeen or will be in full time education,
therefore only occupying the home in the evenings and weekends.
Further advantages that will benefit the project and the client include reduced environmental
nuisance, factory controlled quality assurance, reduced risk exposure from reduced on site
labour, reduced construction waste through efficient controlled manufacturing and the result
of an engineered final product.
Negative views shared by some in the construction industry of the UK that can be ruled out,
include the limitation of only the traditional procurement process that has been
recommended anyway and the lack of experienced builders and erection crews. This is not
true because the increase of popularity of timber frame construction in the Aberdeen area
has meant that more experienced erection crews are in place and better techniques are being
used. Another potential problem is the susceptibility to decay of timber when exposed to
excessive moisture (potential flooding) but this can be overcome through the use of VCL,
damp proof material (DPM) and damp proof course (DPC).
It recommended that suspended timber flooring is used when building off ground with low
load bearing capacity. Also, by separating the floor from the ground and having the flexibility
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to raise the finished floor level throughout the design process, extra protection from any
potential flooding can be obtained.
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6.0 Building Services
6.1 Heating
To help the proposed development become approved by the planning department and be
deemed as a sustainable home, a wood pellet boiler will be incorporated alongside electric
heating. This innovative system will be used to provide hot water and some general heating,
whilst electric radiators will heat the rest of the home when necessary. By using a wood
pellet burner, the burning of oil can be eliminated from the new build which will have a
positive impact on the environment, as low carbon emissions are produced. Other benefits of
this system include high efficiency and reduced fuel costs when compared to oil burners,
especially in an area where wood pellets are widely available. In order to optimise the
efficiency of the boiler, a purpose built store will be incorporated into the design to ensure
moisture levels of wood pellets are kept low at all times. It is recommended for economical
value that a store capable of holding a 3 tonne minimum bulk delivery is constructed,
approximately 2.4m x 2.4m with a minimum ceiling height of 2.4m.
6.2 Electricity
An application will need to be made to Scottish and Southern Energy, the supplier of
electricity throughout Scotland, for a new connection to be made to the existing main. This
application will include site location plan and proposed meter location.
6.3 Water & Drainage
To be connected to the water main, an application to Scottish Water, a statutory corporation
in Scotland that provides water and sewerage services, must be made. A connection to the
existing main should not be a problem, as it already provides for the existing home. Foul
drainage for the proposed development will be disposed in the existing septic tanks which
have recently been replaced and are more than sufficient for the existing building. Surface
water from house and landscape will be diverted to existing water course, by incorporating
appropriate SuDS to reduce potential flood risk and please Scottish Water and local authority.
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7.0 Material Specification
7.1 Introduction
All specification provided is relevant for the extent of wall shown on dwg 0001 and some of
bedroom 2 as a whole. Standard Method of Measurement of Building Works: Seventh
Addition has been considered where applicable and all materials have been chosen with
sustainability in mind.
7.2 Specification
F10 Brick/block walling
Blockwork External Leaf (£0.97 per block / 72 per pallet)
Blocks: 100mm Solid lightweight Readyblock, standard finish, to BS EN 771-3: 2003 as
manufactured by Cemex
Minimum average compressive strength 7.3N/mm²
Mortar 1:1:6 cement, lime, sand. (Joints to be raked out to a depth of 15mm to provide key
for render)
Blockwork Below DPC Level Internal Leaf (£150/M²)
Blocks: 150mm thick lightweight block (Blocks Shield), standard finish to BS EN 771-3: 2003 as
manufactured by Thermalite.
Minimum average compressive strength 3.6N/mm²
Mortar 1:1:6 cement, lime, sand
F20 Natural Stone Rubble Walling
Stone External Leaf
Stone: 100mm course of sandstone, random sizes to BS 5628-3:2005 as manufactured by Kirk
Natural Stone. (1 Pallet approx 2m² - £50)
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Minimum average compressive strength 2.2N/mm²
Mortar 1:1:6 cement, lime, sand
Sill: 140x175 Stone Sill Manufactured by Kirk Natural Stone (2000mm - £68.25)
F30 Accessories/Sundry Items for Brick/Block/Stone Walling
51mm Thick Cavity: 175mm Staifix Timber Frame Tie, Wall Ties to BS 5268-6.1 Type 6* Tie @
600 crs. (50p)
30x5mm TFS/HD/900 Timber Frame Holding Down Straps to BS EN 1034:2009 (G275) as
manufactured by BPC fixings (£3.50) @2000 crs.
F31 Precast Concrete Sills/Lintels/Copings/Features
Lintel: 102x183 (Nominal Height) Steel Standard Duty CTF5 lintel to BS EN 845-2:2003 as
manufactured by Catnic. (2100mm - £20.04)
G20 Carpentry/Timber Framing/First Fixing
Timber Frame Internal Leaf: ‘Gold Closed Panel’ construction; reflective breather membrane,
9mm OSB sheathing, 140mm framing, 140mm polyurethane insulation, reflective vapour
control layer, 25mm service void/battens, 12.5mm tapered edge plasterboard (Aprox.
£300/m² & to achieve 1.5W/m²K) to BS 5268-6.2:2001 as manufactured by Scotframe
H62 Natural Slate
Slate: 300x200mm SIGA Natural Slate with 80mm headlap at 30° pitch to BS EN 1236:2004 as
manufactured by SIG Roofing, on 50x25 treated timber battens on breather membrane &
sarking (£73/m² including labour).
Duo Pitch Trusses: Scotframe ‘Gold Closed Panel’ construction; 420mm Frametherm Insulation
(0.10 W/m²K)
40 INSULATI
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L10 Windows
Window: 1800x1360 Brushed aluminium window with hardwood trim, vacuum preservative
treated, as manufactured by AB Windows (£1500)
Top hung opening casements glazed with double glazed clear glass to BS 952: Part 1: 1995 &
BS 5713 199, Brushed aluminium handles
M20 Rendered Coatings
External Render: To comply with BS EN 13914-1- External Rendering
Proprietary cement gauged render, fine textured finish
Total Thickness 12mm (£45/m² inc. labour)
R10 Rainwater Pipework/Gutters
Gutters: Marley or equal, uPVC half round type with snap joints in the running length; fixing
with standard fascia brackets at 1m crs, Pipes 75mm∅plastic fixed at 2000mm crs
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Timesing Dimension Squaring Description
4.50
2.26 10.17
Blockwork
100mm Lightweight Ready Block, standard finish, to
BS EN 771-3:2003 as manufactured by Cemex,
Mortar 1:1:6 cement, lime, sand (m²) F10
1.80
1.26 (2.27)
Deduct
Window (m²)
7.90
4.50
0.18 0.81
Stone External Leaf
100mm course of sandstone, random sizes to BS
5628-3:2005 as manufactured by Kirk Natural Stone,
Mortar 1:1:6 cement, lime, sand (m²) F20
1
Sill
140x175 Stone Sill Manufactured by Kirk Natural
Stone (2000mm long) (nr)
6/ 8 48
Forming Cavity
175mm Stafix Timber Frame Tie, wall ties to BS 5268-
6.1 Type 6* Tie, 8 ties horizontally, 6 ties vertically
(nr) (F30)
2
Forming Cavity
30x5mm TFS/HD/900 Timber Frame Holding Down
Straps to BS EN 1034:2009 (G275) as manufactured
by BPC fixings (nr) (F30)
1
Lintel
102x183 Steel Standard Duty CTF5 lintel to BS EN
845-2:2003 as manufactured by Catnic
4.50
DPC
100mm wide polythene DPC at External Leaf as
manufactured by Visqueen (m) (F30)
1
Window
1800x1260 brushed aluminium window with
hardwood trim, vacuum preservative treated, top
hung casements double glazed with clear glass to BS
952: Part 1:1995 & BS 5713:1994 as manufactured
by AB windows (nr) (L10)
4.50
2.10 9.45
Render
12mm thick proprietary cement gauged render, fine
textured finish, to comply with BS EN 13914-1-
External Rendering (m²)
HNC Construction - Graded Unit
7.3 Dimension Paper
23
Blockwork Outer Leaf
100mm Solid lightweight Readyblock delivered to site per 72 £69.84
Wastage 5% £3.49
£73.33Labour: 2 bricklayers per hour @ £10.00 £20.00
1 labourer per hour @ £6.50 £6.50
Squad Cost £26.50
Output per tradesman 40 block / hour
Cost of Labour per 72 blocks 72 x £26.50 £23.85
2 x 40
Mortar @ £109/m³ @ 0.072m³ per 72 blocks £7.85
Cost for 72 blocks £105.03
Number of blocks per m² for outer leaf is 10
Cost per m²: £105.03 x 10 £14.59
72Profit and oncost @ 20% £2.92
£17.51
Stone Outer Leaf
100mm course of sandstone, random sizes delivered to site 1 pallet = 2m² £50.00
Labour: 2 bricklayers per hour @ £10.00 £20.001 labourer per hour @ £6.50 £6.50
Squad Cost £26.50
Output per tradesman 30 stones per hour
Cost of Labour per 100 stones 100 x £26.50 £44.17
2 x 30
Mortar @ £109/m³ @ 0.12m³ per 100 stones £12.00
Cost for labour & mortar for 100 stones £56.17
Number of stones per m² for outer leaf is 20
Cost per m²: £56.17 x 20 £11.24
100
Cost per m² for stones 50 £25.00
2 £36.24
Profit and oncost @ 20% £7.25
£43.49
Sill
140x175 Stone Sill Manufactured by Kirk Natural Stone (2000mm long) £68.25
Cost of Labour (2 Tradesman @ £10.00) £2.00
£70.25
Profit and oncost @ 20% £14.05
£84.30
HNC Construction - Graded Unit
7.4 Rates
24
Wall Ties
175mm Staifix Timber Frame Tie £0.50
Cost of Labour per tie (1 Tradesman @ £10.00) £0.50
£1.00
Profit and oncost @ 20% £0.20
£1.20
Holding Down Straps
30x5mm TFS/HD/900 Timber Frame Holding Down Straps £3.50
Cost of Labour per strap (1 Tradesman @ £10.00) £1.00
£4.50
Profit and oncost @ 20% £0.90
£5.40
DPC
100mm wide polythene DPC delivered to site per 32m roll £3.95
Labour: 1 bricklayer per hour @ £10.00
Output per tradesman 10m per hour
Cost of Labour per 32m roll 32 x £10.00 £32.00
10 £35.95
Cost per m £35.95 £1.1332
Profit and oncost @ 20% £0.23
£1.36
Lintel
Cost of Labour (2 Tradesman @ £10.00) £2.00
£22.04
Profit and oncost @ 20% £4.41
£26.45
Window
1800x1260 brushed aluminium window delivered to site per unit £1,500.00
Cost of Labour (2 Tradesman @ £10.00) £70.00
£1,570.00
Profit and oncost @ 20% £314.00
£1,884.00
Rendered Coating
12mm thick proprietary cement gauged render (labour, material and £45.00
profit) per m²
25
Note: Quantities taken only for wall shown on plan, above & including DPC & excluding Scotframe kit
Unit Quantity Rate £ p
F Masonry
F10 Brick/Block Walling
a
Blockwork External Leaf
100mm Lightweight Ready Block, standard finish,
to BS EN 771-3:2003 as
Manufactured by Cemex
Mortar 1:1:6 cement, lime, sand m² 10.17 17.51 178 08
F20 Natural Stone Rubble Walling
b
Stone External Leaf
100mm course of sandstone, random sizes to BS
5628-3:2005 as manufactured
by Kirk Natural Stone
Mortar 1:1:6 cement, lime, sand m² 0.81 43.49 35 23
F20 Natural Stone Rubble Walling
c
140x175 Stone Sill Manufactured by Kirk Natural
Stone (2000mm long) nr 1 84.30 84 30
F30 Accessories/Sundry Items for Brick/
Block/Stone Walling
c
Forming Cavity
175mm Stafix Timber Frame Tie, TIM6 wall ties
to BS 5268-6.1 Type 6* Tie nr 48 1.20 57 60
F30 Accessories/Sundry Items for Brick/
Block/Stone Walling
d
30x5mm TFS/HD/900 Timber Frame Holding
Down Straps to BS EN 1034:2009 (G275) as
manufactured by BPC fixings nr 2 5.40 10 80
F30 Accessories/Sundry Items for Brick/
Block/Stone Walling
e
100mm wide polythene DPC at External Leaf as
manufactured by Visqueen m 4.50 1.36 6 12
f
F31 Precast Concrete Sills/Lintels
/Copings/Features
102x183 Steel Standard Duty CTF5 lintel to BS EN
845-2:2003 as manufactured by Catnic nr 1 26.45 26 45
L Windows/Doors/Stairs
L10 Windows
g
1800x1260 brushed aluminium window with
hardwood trim, vacuum preservative treated,
top hung casements double glazed with clear
glass to BS 952: Part 1:1995 & BS 5713:1994 as
manufactured by AB windows nr 1 1,884.00 1,884 00
M Surface Finishes
M20 Rendered Coatings
h
12mm thick proprietary cement gauged render,
fine textured finish, to comply with BS EN 13914-
1-External Rendering m² 9.45 45 425 25
Total 2707 83
HNC Construction - Graded Unit
7.5 Bill of Quantities
26
(x) (λ) (R = x/λ)
External Surface - - 0.060
External Render 0.012 0.500 0.024
Exernal Blockwork 0.100 0.380 0.263
Cavity - - 0.180
OSB 0.009 0.013 0.692
PU Insulation 0.140 0.022 6.364
Service Void - - 0.090
Plasterboard 0.013 0.160 0.078
Internal Surface - - 0.120
Total Resistance (ΣR) 7.871
U-value = 1/ΣR = 1/7.871 = 0.127 W/m²K
Note: Thermal bridging has not been accounted for, therefore a U-value of 0.15 W/m²K is realistic
Fabric Heat Loss Calculation: Qf = ΣUA(Ta-Tb)
Area (m²)
14.10
14.10
26.10
2.45
Note: Design internal temperature is 20°C & an external temperature of 0°C has been assumed
Ventilation Heat Loss Calculation: Qv =
Qv =
Qv =
Note: Based on 2 air changes per hour and the assumption of 1200 J/m³K for the specific heat capacity of air
Total Heat Loss = 235.66 + 112.8
= 348.46 W
3600
112.8W
Cv NV(Ta-Tb)
3600
1200 x 0.5 x 33.84 x 20
0.10
Total Heat Loss from Bedroom 2
HNC Construction - Graded Unit
7.6 Heat Loss Calculations
Justifying Scotframe 'Gold Closed Panel' Wall Construction 0.15W/m²K)
Thickness (m) Thermal Conductivity Thermal Resistance
0.18
0.35
0.70
3.30
0.70
Roof
Wall
Windows/Doors
0.18
0.25
1.80
0.15
1.60
Building Regulations Maximum Values
Area-Weighted AverageType of Element Individual Element Proposed U-value
Floor 0.20
Type of Element
Floor
Roof
Wall
Windows
Temperature
Difference (°C)U-value (W/m²k) Heat Loss (W)
0.18
0.10
0.15
1.60
20
20
Total Fabric Heat Loss 235.66W
20
20
50.76
28.20
78.30
78.40
27
HNC Construction: Graded Unit
8.0 Health & Safety - Construction Regulations
The structure in which regulation and enforcement of workplace health and safety within the
UK, is defined by the ‘Health and Safety at Work etc Act 1974’ (HASWA). This act of
parliament sets out the general duties of employers, employees, contractors, persons in
control of work premises and those who manage and maintain them. In the construction
industry, it ‘governs powers of inspectors regarding safe practices on sites together with
contravention of the Construction Regulations.’ These Construction Regulations apply to
building operations and to works of engineering construction and fall under the umbrella of
‘Management of Health and Safety at Work Regulations 1999’, alongside the ‘Control of
Substances Hazardous to Health Act COSHH 2002’.
The principle set of regulations that are of relevance to this project are ‘The Construction
(Design and Management) Regulations 2007’ which are envisaged for a large scope of
construction works. These enable the application and management of Health and Safety at
work to be enforced on site and place responsibility on the client to appoint a CDM
Coordinator and Principle Contractor. The CDM Coordinator is responsible for preparing a
pre-tender, construction phase plan, health and safety file, informing the Health and Safety
Executive (HSE) (administering body), ensuring designers confirm with their health and safety
obligations and that contractors are competent with regard to health and safety matters and
advising client and principle contractor appropriately. The Principle Contractor is then
responsible to develop the construction phase plan, collate relevant information and
preserves it as work continues, administer health and safety issues and cooperate with the
CDM coordinator, designers and site operatives preparing risk assessments throughout. The
designer will also have established that the client is aware of their duties, considered the
design implications with regard to health and safety including risk assessments and have
coordinated CDM work with other members of the design team.
Other vital regulations include ‘The Construction (Head Protection) Regulations 2007’, ‘The
Personal Protective Equipment Regulation 2002’, the ‘Lifting Operations and Lifting
Equipment Regulations 1998’ and ‘The Working at Height Regulations 2005’.
28
HNC Construction: Graded Unit
9.0 Setting Out
9.1 Introduction
To ensure the proposed building is constructed in the accurate position and eliminate any
future problems due to poor alignment, the setting-out process will be used. This task will be
undertaken once a finished ground level of 40.400m that will surround the property has been
achieved and the site has been cleared of any debris or obstructions. The International
Organisation for Standardisation (ISO) define setting out as: Setting out is the establishment
of the marks and lines to define the position and level of the elements for the construction
work so that works may proceed with reference to them. This process may be contrasted with
the purpose of surveying which is to determine by measurement the position of existing
features.
There are different options to choose from when setting-out domestic buildings, including
traditional means of using horizontal dimensions and offsets against a site reference grid or
control points and the modern alternative of using setting out coordinates, using either a
total station or GPS RTK system. Although using these new technologies initially costs more,
the benefits surpass those of the traditional setting out process. These include achieving fast,
precise spot levels, provided they are carried out by a competent site/setting out engineer
and can be achieved independently as opposed to working in pairs. This will speed up
contractor and engineer time on site, therefore benefitting the client when observing the
bigger picture. Therefore it is recommended that the client agrees to using coordinates and a
total station to set out the new build.
9.2 Equipment
• Concrete Nails
• Current Setting Out Coordinates Drawing (Dwg 0023)
• Hammer
• Measuring Tape
29
HNC Construction: Graded Unit
• Pinch Bar
• Target
• Spray Paint
• Steel Tape
• Survey Log
• Total Station
• Tripod
• Wooden Mallet
• Wooden Pegs
9.3 Accuracy
As mentioned previously, achieving high levels accuracy when setting out is paramount. The
British Standard (BS 5964-1:1990, ISO 4463-1:1989) sets out that the accuracy when achieving
spot levels and TBM should be within the following limits:
• Site TBM relative to the MBM ± 0.005m
• Spot Levels on soft surfaces relative to a TBM ± 0.010m
• Spot Levels on hard surfaces relative to a TBM ± 0.005m
It is known however, for site/setting out engineers to work within a 0.002m tolerance when
hammering nails/wooden pegs to ensure that no problems arise during construction. It is the
contractors responsibility to set out the building accurately and who is liable to amend any
works carried out due to poor checking/setting out and compensate for any subsequent fees.
There is greater leniency when setting out foundations as opposed to blockwork, however
care should always be taken by the engineer to provide accurate nailing on site.
9.4 Method
When setting out using a total station it must first be leveled and centered over a first control
point, similarly to how a theodolite would be set up when using older techniques. This control
point will take the form of the TBM already set out on site, that was used to tie back to the
30
HNC Construction: Graded Unit
Ordnance Survey Benchmark near the site when leveling to achieve the 40.400m horizontal
plane for the house to sit on and is marked on the current ‘Setting Out Coordinates &
Dimensions / 0013’ drawing. To centre the total station/tripod directly over the TBM, the
bubble is checked against the centre of the peg. This is crucial, otherwise the subsequent
readings taken with the instrument will not give the correct results. Having been set up
correctly, the total station will then be rotated horizontally to site coordinate system and the
coordinates of the TBM provided by the design engineer will be entered.
Next, the corner of the external building shown on the drawing will used as a reference object
(RO) and the coordinates for the point are also entered into the total station. The ‘horizontal
circle orientation programme’ will automatically calculate the bearing from the total station
to the RO. Having established this orientation, the setting out process can begin by entering
the coordinates of the points shown on the drawing. It is important to ensure all coordinates
are entered exactly as they appear, or the station would provide the wrong location for the
points. The instrument will send the site/setting out engineer along the correct horizontal
distance where the peg/nail should be hammered. The station will then make an
‘observation’ and it will provide exact information on where the peg/nail should be located.
When setting out the foundations, wooden pegs are hammered in place to show where the
ground will be excavated for the deep strips. Each peg is double checked and dimensions
from Peg 1 and Peg x are made from the corners of the existing building using the tape. The
tape will first be checked against the steel tape to ensure it has not been stretched and
measurements made are accurate.
When the site/setting out engineer returns to site after the foundations have been poured
and set, the nails to position the blockwork will be hammered in. The process would be
exactly the same as before, however extra care will be taken to ensure that blockwork is built
in the correct position. It is important that the target is kept on each nail and rechecked to
ensure that it has been hammered in vertically and accurately. Distance between nails will be
checked with steel tape against dimensions from dwg 0011 & 0012 and if any discrepancies
31
HNC Construction: Graded Unit
are found, it is recommended that process is carried out again. Once checks have been made
and the engineer is satisfied, the nails are sprayed to ensure tradesman can find them.
9.5 Conclusion
Therefore, the setting out process using the total station has been recommended and
explained. This will allow the building to be set out accurately and efficiently and will allow
construction works to continue smoothly and on schedule. The importance of accurate
setting out has been explained and it is recommended that a competent and reputable
site/setting out engineer is chosen to carry out the task.
32
HNC Construction: Graded Unit
10.0 References
Roy Chudley & Roger Greeno (2013) Building Construction Handbook. 9th
Edition. Milton Park,
Abignton, Oxon. Routledge.
Unknown(2014)Planning Available at:
http://www.aberdeencity.gov.uk/planning_environment/planning_and_environment.asp
(Accessed: 05/02/14)
Unknown(2014)Planning Available at: www.esplanning.scotland.gov.uk (Accessed: 05/02/14)
Unkown(2014) Building Regulations
http://www.planningportal.gov.uk/permission/responsibilities/buildingregulations/difference
13/02/14 (Accessed: 08/02/14)
Unkown(2014) Building Standards
https://www.aberdeencity.gov.uk/planning_environment/building_standards/bld_BuildStand
ards.asp (Accessed: 08/02/14)
Unknown(2014)Building Standards Available at:
https://www.aberdeencity.gov.uk/planning_environment/building_standards/bld_BuildStand
ards.asp (Accessed: 12/02/14)
Costclick(2014)Floors-Solid/Suspended/Ground/First available at
http://www.costclick.co.uk/Floor-ground-suspended-first.asp (Accessed: 15/02/14)
Home Building & Renovating (2014) Comparing Masonary & Timber available at
http://www.homebuilding.co.uk/advice/key-choices/structural/compare-masonry-timber
(Accessed: 15/02/14)
33
HNC Construction: Graded Unit
Julian Owen (2013) Pros and Cons of Timber Frame Construction available at
http://www.constructionchat.co.uk/articles/timber-frame-buildings/ (Accessed:15/02/14)
Scottish & Southern Energy (2014) available at
http://www.ssepd.co.uk/Connections/SmallProjects/Apply/(Accessed: 17/02/14)
Alternative Heat (2014) available at http://www.alternativeheat.co.uk (Accessed: 17/02/14)
Unknown (2014) available at http://www.scotland.gov.uk/Resource/Doc/217736/0093791.pdf
- natural stone masonry in modern Scottish construction - A guide for designers and
constructors – (Accessed 03/04/14)
Unknown (2014) available at http://www.plasterersforum.com (Accessed 03/04/14)
Unknown (2014) available at http://www.cemex.co.uk/readyblocklightweightblock.aspx –
(Accessed 03/04/14)
Unknown (2014) available at http://www.kirknaturalstone.com – (Accessed 03/04/14)
Scotframe (2014) available at
http://www.scotframe.co.uk/MainlandUK/KitSpecification/Thermal-Kit-Specification.aspx –
(Accessed10/04/14)
Unknown (2014) available at
http://www.scotframe.co.uk/MainlandUK/PriceGuides/PriceGuide.aspx – (Accessed 10/04/14)
Unknown (2014) available at http://www.sigroofing.co.uk/downloads/naturalslate.pdf –
(Accessed10/04/14)
Unknown (2014) available at http://www.fixmyroof.co.uk/videos-and-guides/pitched-
roof/roofing-prices/ – (Accessed 17/04/14)
34
HNC Construction: Graded Unit
Unknown (2014) available at http://www.online-building-supplies.co.uk/100mm-7n-solid-
dense-concrete-breeze-block-42-p.asp – (Accessed 17/04/14)
Unknown (2014) available at http://www.truetradesman.co.uk/index_files/Page324.htm –
(Accessed 17/04/14)
Unknown (2014) available at http://source4me.co.uk/calculate_brick_block_mortar.php –
(Accessed 17/04/14)
Unknown (2014) available at http://www.safestyle-windows.co.uk/customer-care/ask-an-
expert/fitting/how-long-will-it-take-to-install-new-windows-and-doors/ – (Accessed 17/04/14)
35
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