wall

Reports investigation of airtightness of two types of industrial wall when subjected to a differential pressure across the wall construction. Laboratory tests were performed on wall units, overlap joints in vapour barriers of plastic sheet,on steel stud wall with metal sheeting and joints in the light- weight concrete element wall being studied. Shows that methods of construction employed so far can be retained if modifications are made concerning junctions and the sealing of joints. In sheet metal walls, the contact pressure onto the plastic foil must be guaranteed.

Describes research project to find air leakage values of walls of elevator and stair shafts in order to use these values in the design of pressurization systems. Describes method of test and gives results. Concludes that leakage rates for walls of elevator shafts constructed of masonary units are higher than those of cast-in-place concrete. Variations in the leakage of stair shafts could not be related to the type of wall construction but probably depended on the workmanship in sealing crack openings.

Describes apparatus used to measure air leakage through windows. Gives details of windows with and without weatherstripping. Gives results in the form of graphs in two sections. 

Reports tests made to determine the air leakage characteristics of various types of walls. Describes apparatus and method and gives results of tests on brick, wood frame, stucco and brick and tile walls, with and without plaster, paint and caulking. Finds that air leakage characteristics alter with the age of the wall, that paint alone did not greatly reduce the leakage of the brick wall, but that plaster was very effective. Also gives data for leakage between plaster or stucco and wood frame.

Describes test apparatus and procedure and gives results of air leakage tests on various types of wood frame construction. Also gives the results of tests on the effect of adding sheathing paper, plaster, wall paper and paint. Concludes that air leakage through a frame wall construction containing building paper or plaster properly applied is negligibly small. Single-surfaced walls showed considerable leakage.

The significance of air tightness on building performance and the factors affecting the air leakage performance of the building enclosure are discussed. the ability of the ASTM standard air leakage test method to check the quality of design and manufacture of factory-assembled walls, windows and doors as well as the inability of the method to provide the building designer with quantitative air leakage data for calculating heating and cooling loads and designing smoke control means is also discussed.

Describes the influence on heat resistance of an insulated wall of workmanship and forced convection. Compares experimental investigations on cross-bar walls with calculated values. Examples show the influence on heat resistance of insulation installation, air-flow along the insulation and air-flow through the insulation. Concludes that air-tightness of the vapour barrier and partly of the inside board are of great importance.

Reviews means of rain water penetration and how to apply one-stage weather proofing listing the disadvantages. Reviews research results obtained with two-stage weather proofing by adding an additional seal and summarises the pressure variations resulting from wind plus the design of horizontal and vertical joints between individual facade segments. Discusses the practical design of joint and sealant illustrating this for a few window types and adds that this design is also applicable for a complete curtain wall.

Discusses basic physical features of combined energy and moisture flow in porous building material. Discusses mathematical and physical structure of these dynamic processes in terms of local thermodynamic equilibrium, flows induced by gradients in intensive state variables and conservation of energy, moisture and other components. Gives conditions for thermodynamic equilibrium, discusses peculiarities of pore-water tension, and problems concerning energy flow. Deals with the causes of hysteresis and the complications due to hysteresis.

Summarises data on air flow characteristics of walls from U.S.A. and Norway. Reports laboratory measurements on four test walls and identifies main sources of leakage for the different test facades. Average air leakage at 200 Pa varied from 5m3/h/m2 to 50m3/h/m2. Shows that wall leakage rate could provide 30% or more of the total leakage rate.