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Table of Contents 1. Introduction 2

1.1.Introduction to the site 2

2. Site investigation and ground reports 2

2.1.Site Investigation 3

2.2.Ground Works 4

3. Foundations 4

4. External Walls 5

5. Floors 6

6. Roofs 8

7. Conclusion 9

1. INTRODUCTION

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The report intends to draw necessary attention towards the construction details for the chosen site

located at Church Fields Garston L19 8NG. The details will encompass site investigation report,

the insight to the construction aspects of the site including the ground works, foundations,

external walls, floors and roofs.

1.1.Introduction to the Site

The location of site is approximately five miles to the South-East of Liverpool, close to the river

Mersey and Garston Docks at Church Fields. The area is crowded with mostly 2 story houses.

The report is also intended for construction of a house at the aforesaid location.

2. Site Investigation & Ground Works

The site investigation is the preliminary phase for analyzing the architectural and urban design of

a site while considering the geographical, climatic, and infrastructural and safety context of a

specific site. It will assist in the selection of the foundations laid down beneath the superstructure

of the building along with the overall design of the site under construction scrutiny.

Before designing a foundation, there must be a reasonably accurate conception regarding the

physical properties and arrangements for the subject materials. The fields investigations is the

process by which the hazards present in the ground beneath the site are explored and reported.

2.1. Site Investigation

On the basis of location of the chosen site, the below mentioned information is crucial for

consideration while execution of the construction project.

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- The type of structure to be built: Since, the site is intended to be utilized for

construction of two story house. Therefore, among the forms of low rise construction

including timber frame, steel frame, concrete frame, load bearing, single story the most

preferable is the timber frame as it seems to be cost effective as well light and provide

considerable strength to the structure.

- Characteristics of the structure: The decision about structure of the building is

followed by the understanding the design of the foundation to be laid underneath the

ground.

- Soil Investigation: The geo technical or aerial analysis of the soil condition at the site is

essential which is covered in the important points highlighted in the subsurface

investigation.

o Subsurface Investigation

✓ The sequence and nature of strata.

✓ The conditions of ground water at the site.

✓ The assessment of physical properties of rock and soil of the concerned site.

✓ The characteristics of foundation of adjacent structure and the chemical

composition of ground water.

- Foundation Design: The foundation structures include deep foundation and shallow

foundations. The deep foundations are used for heavy buildings, while the shallow ones

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are used for light buildings like in this case houses. The shallow foundations are also

called spread footings or open footings. Each footing takes the concentrated load and

spread it over larger area to not let the weight exerted on the soil to exceed the capacity of

safe bearing of soil.

2.2. Ground Works

The methods of investigations of ground conditions include trial pits and boreholes. The trial

pits entails shallow excavations going down to a maximum depth of 6m. The trial pit excavation

methods includes by hand with depth of up to 2 m, wheeled back hoe till 4m and finally

hydraulic excavator with up to 4-6 m depth. The trial pit requires information pertaining to

location, size of pit, depth scale, root structure, water level and seepage. The weather conditions

also do impact the soil conditions which need to be under consideration. The process of

grounding must follow some necessary safety precautions w.r.t. health safety as well as ensuring

strength of the future foundations and designs. This requires water elimination and ground

improvement. The safety considerations while laying down foundations must consider the

freezing weather as it should be built below the frost line which is the level in the ground above

where the freezing occurs.

3. Foundations

The shallow foundation includes strip footings which entails a strip of concrete that supports the

weight of an entire wall. Such striping’s are used where the building load is carried by entire wall

compared to the isolated columns. The project will use deep strip foundations considering the

reach to the soil is at lower level with suitable bearing capacity. The deeper trench is dug and

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strip foundations are poured at a lower level which holds the weight of walls built at the ground

level.

3.1. Method Statement Activities for construction of Trench Fill Strip Foundation

1) First, the excavation lines are setup.

2) Scanning of area will be carried out using Cable Avoidance tool.

3) The excavation of trench will be carried out with constant monitoring for excavation

level until the desired depth is achieved.

4) Concrete will be discharged on the trench from the concerned equipment or source.

5) The vibration of concrete at constant level will be assessed to ensure attainment at

appropriate level,

6) A level surface is ensured by tamping of concrete.

7) Post pour checks are taken to assess that line and level are within contract tolerances.

4. External Walls

The execution of foundation laying plan is followed by the development of external masonry

walls. The important materials used for the construction of external walls include solid

concrete masonry blocks, cement, damp proof course, scaffolding platforms, steel masonry

accessories etc. The masonry cavity wall composed of two pieces of masonry separated by an

air space connected by corrosion-resistant metal ties. The inner leaf is solid concrete block

and the outer leaf comprised of bricks. The Earthwool Dri Therm Cavity Slabs are light

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weight semi rigid slabs of glass mineral wool with water repellent additive to produce a fit

between wall ties at standard vertical spacing. Damp proof courses are installed to ensure that

penetrating water is directed to the outer leaf.

The establishment of external walls initiates from the foundations. The wall starts from

beneath the ground while the cavity wall is established above the ground by creating gap

through cavity insulation. The Damp Proof Membrane is set before the rigid insulation piece

to separate it from the concrete at the ground floor.

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Source: Chudley & Greeno (2008), pg # 217

Ground Level

1500 m

1000 m

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!

Source: Chudley & Greeno (2008), pg. 402

5. Floors

The construction of upper floor is much simpler as it requires a level smooth surface capable of

supporting required dead and imposed loads. The element of fire construction amid sound

resistance must be safeguarded. The upper floor plays an important role in providing lateral

resistance to external walls. The method for construction of upper floor is not changed drastically

with the traditional practice as still the joists supporting floor covering with finish on the

underside. The floors are formed with wood joists covered above with floor boards and beneath

with wood laths and plaster. The joists have to be trimmed around all fireplaces and for stair

wells and other openings.

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!

Source: Chudley & Greeno (2008), pg. 416

The timber frame is a modernized construction method which employs standardized

prefabricated timber wall panels and floors. The timber frame design considers the building

regulation requirement for thermal, acoustic and fire proofing ensuring safety measures in the

floor designing process. Key health and safety requirements for timber frame utilization are as

following:

- Construction (Design and Management) Regulations

- Risk Assessments

- Full Scaffolding

- Fall prevention and arrest methodologies

- Control of lifting operations

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- Site security

- Manual Handling

6. Roofs

The flat roofs traditionally consist of a structural timber deck with water proof covering directly

applied to the top of the deck. The cold deck flat roof does incorporate insulation in the form of

mineral wool which is stuffed in between the timber rafter / joists with a minimum air gap of 50

mm (2inch) left in between the insulation and roof deck. Whereas the warm deck flat roof is

resulted through moving the insulation to the outside of the structure. While, the roof deck is

brought inside. The purpose is the possibility of condensation forming on the underside of the

deck and eliminates damp. This design accommodates for conserving heat thus no need of

ventilation. In the cold roof the good ventilation is essential to allow condensation to escape

particularly where moisture levels are high.

Most roofs are prepared with trussed rafters. In the case of timber frame, the head binder of the

wall panels provides a ready fixed level and straight wall plate where to fix the trussed rafters.

The timber frame provides a secure fixing point for truss clips, straps and bracing. Trussed rafter

roofs can be assembled in sections on the safe working platform of a lower cassette floor. The

part assembled roof can then be lifted off in sections, placed temporarily at ground level (often

on the ground floor slab of an adjacent plot) while the final story of wall panels are erected.

When this stage is complete the roof can be lifted back on again (in sections if necessary), fully

braced, and then fixed with felt and tiling battens. Aside from the obvious advantages in reduced

working at height, this method ensures a perfect fit to the roof.

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7. Conclusion

The report covers the construction details for the site located at Church Fields Garston L19

8NG.The construction designs have been reported to highlight various construction aspects of

the site including the ground works i.e. foundations, external walls, floors and roofs. Deep strip

foundations have been used to lay the structure of the house bearing its whole weight, The timber

frame is employed for flooring purpose.

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References List

Chudley, R. and Greeno, R. (2008) “Building Construction Handbook” Seventh Edition, Elsevier

Ltd.

Emmitt, S. & Gorse, C. (2006) 'Barry's Introduction to the Construction of Buildings' 1st Edition

Blackwell 1405110554 ,

http://buildersafety.org/method-statement-for-concrete-foundations/

M. J. Dumbleton and G. West, Transport And Road Research Laboratory Report

LR403, Preliminary Sources of Information for Site Investigation In Britain (Crowthorne, 1971)

Riley, M. & Cotgrave, A. (2008) 'Construction Technology 1: House Construction' 2nd Edition

Palgrave 978023023624