THE

backofen CEILINGPLASTER AND LATHE

RESTAURANT DESIGN

LATH AND PLASTER IS A BUILDING PROCESS USED TO FINISH MAINLY INTERIOR WALLS AND CEILINGS.

AN ADVANTAGE OF USING LATH IS FOR OR NAMENT AL OR UNUSUAL SHAPES . FOR INSTANCE, BUILDING A ROUNDED WALL WOULD BE DIFFICULT IF DRYWALL WERE

USED EXCLUSIVELY, AS DRYWALL IS NOT FLEXIBLE ENOUGH TO ALLOW TIGHT RADII.

BACKOFEN 'S CEILING HAS BEEN INSTALLED THE TRADITIONAL LATH AND PLASTER. THESE MATERIALS HAVE SUPER IOR SOUND-PR OOF ING QUALITIES WHEN USED WITH

LIME PLASTER WHICH IS DENSER THAN MODERN GYPSUM BOARD.

PLASTER & LATHE CEILING HAVE A MAJOR ROLE FOR THE PR EVENT ION OF F IR E SPR EAD . " THEY ARE CRITICAL TO THE PROTECTION OF HORIZONTAL ELEMENTS SUCH AS TIMBER JOISTED

FLOOR, INCLUDING THE FLOORING ON TOP, WHICH IN TERMS OF THE FIRE PERFORMANCE IS OFTEN IN APOOR CONDITION DUE TO THE PRESENCE OF GAPS "

PLASTER & LATH

MATERIALS USED

Ceilings were usually made using the lath and plaster attached to

wooden joists.

The laths are thin strips of wood (typically about 25mm by 6mm (1 by 1/4

inch) nailed to the underside of the timber joists with a gap of about

6mm (1/4 inch) between each lath.

The plaster was traditionally applied to the laths in three lime puttylayers:

The first layer (aka the render layer) was forced into the gaps between the laths to obtain astrong bond to the laths, this layer was typically about 6mm (1/4 inch) thick.

The second layer (aka the floating coating) to be applied provided the relatively smooth finishfor the third layer, this layer was typically about 6mm (1/4 inch) thick.

The third and final layer (aka the setting layer) provided smooth finish suitable for decoration(typically the finish was whitewash or distemper), this layer was typically about 3mm(1/8 inch) thick.

HOWEVER, Installing lath and plaster ceilings required skilled workers

and was time consuming; they were largely replaced by the use of pre-

manufactured plasterboard when it became widely available in the

middle

of the twentieth century.

Gypsum lath is commonlyused in place of wood sinceit is non-combustible, easyto use, and gives betterresults. The popularity ofthe lath and plaster methoddeclined in the 1950s, as itwas replaced by the lessexpensive drywall method.

Gypsum lath is available witha foil facing which acts asa vapor barrier and heatreflector, and as a veneerbase for plaster veneer.

LATH

Plaster is a buildingmaterial used forcoating walls andceilings. Plaster is

manufactured as adry powder and ismixed with water toform a paste whenused. The reactionwith water liberates

heat throughcrystallization and thehydrated plaster then

hardens. 

PLASTER