▲ Figure 6
Sand - cement screed being applied to ▲ Figure 7-Absence of thermal patterning on urethane foam slabs covering the concrete roof surface.
thermal insulation without being heavy or bulky. They can be fac- tory-prepared under controlled con- ditions, with facing materials select- ed to suit the requirements of the building design. Thus the panels used in the entrance to the Blackley building comprised ain. urethane foam core with a in. ceramic tile exterior facing and in. asbestos board faced with veneered plywood on the interior surface.
Floorand Roof Insulation
The foam applications so
far discussed are typical of
typical of circum- stances that might arise in the con- version of old buildings to new standards of thermal insulation. The techniques now to be described are of particular advantage in new buildings and involve (1) preven- tion of heat loss through the floor into the ground beneath the build. ing. and (2) prevention of losses
104
through the ceilings of the top floor
rooms.
urethane foam - treated wall, compared with standard wall (left).
and the footmarks over the laminates show clearly that they can withstand the usual hazards of construction conditions. levelled
In regard to the first of these, the hardcore foundation was off with a layer of lean concrete and this in turn was sealed with a coating of "Synthaprufe" (National Coal Board) coal tar/rubber com- position. Paper-backed rigid urethane foam laminates (made from  Daltolac 41/Suprasec D/ Arcton 11 recipe), measuring 1 in. thick by 28 in. wide and cut to suitable length. were then placed on to the concrete. the joints were taped, and the whole was covered with "Visqueen" sheeting. before the final layer of 4 in. of reinforced concrete was applied. This was fol- lowed by a screed in which were embedded pipes carrying hot water for underfloor heating, and the floor was finished with vinyl tiles. Figure 5 shows the foam laminates in place during the installation of the floor.
were
Paper-backed rigid urethane foam laminates
employed in a similar manner to insulate the roof of the building. The foamboard was laid on the concrete roof slab and covered with a "Visqueen" inter- layer. A sand/cement screed (Figure 6) was then applied so as to provide drainage falls, and the roof was then finished with a double layer of asphalt. Here again, it is evident that the foamboard is a robust form of insulation ideally suited to this type of work.
Miscellaneus Applications
All the foregoing applications concern the use of urethane foam as thermal insulant applied during the (Continued on page 106)
THE HONG KONG & FAR EAST BUILDER-VOLUME 18. NUMBER 2
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