Effects of velocity distribution on wind loads and flow patterns on buildings.

Discusses pressure distribution on buildings. Describes wind tunnel tests on model buildings. Pressure distribution on walls were measured in a constant velocity field and in anartificially produced velocity gradient. Discusses results and deduces rules by which pressure distribution and wind loads can be predicted for buildings in any specified wind field. Changes in the flow pattern due to the velocity distribution were observed and correlated with the pressure distribution.

Air infiltration into heated buildings.

Gives method for calculating air infiltration through window cracks. Calculates pressure drops across windows in buildings for four types of building and discusses resulting pressure differences. Gives values for crack width and length. Recommends design values for rates of air change due to infiltration in buildings heated by off-peak electricity.

Roughness element geometry required for wind tunnel simulations of the atmospheric wind.

Describes method of estimating roughness required to generate velocity profile of a given shape with a boundary layer of agiven depth. Uses data correlation for the wall stress associated with very rough boundaries and a semi-empirical calculation method to calculate the shape of boundary layers in exact equilibrium with the roughness beneath them. Results can be summarized in a single figure which relates shape factor of boundary layer to height of roughness elements and their spacing

Natural ventilation of buildings

Reports model scale experiments to investigate the validity of digital analogue methods of predicting natural ventilation. Finds calculated ventilation rates up to 30% higher than observed model ventilation rates. Shows differences between observed and computed results caused by operating efficiency of ventilation openings being less than calibrated efficiencies. Corrected ventilation rates, allowing for changes in efficiency due to pressure fluctuations and lateral air flows over model surfaces showed close agreement with observed results.

New ways with weatherproof joints.

Reports tests using a natural exposure rig on a number of designs of horizontal and vertical joints employing labyrinths to separate the air and water entering the joint. Results obtained under a limited range of conditions show that it is possible, with suitable designs, to prevent penetration of water without necessarily making a joint airtight. Puts forward a number of potential applications, including a prototype window.

Open-jointed rain screen claddings

Reports natural exposure test on vertical joints in open-jointed rain screen cladding. Describes test rig and gives results of water penetration tests. Gives design recommendations for screens.

Window to wall joints

Discusses some problems of providing weathertight joints between window and wall. Mentions sealing failures, condensation, frame defects and poor dpc detailing as important reasons for water penetration around windows. Refers to some principles of weather protection. Makes recommendations for the design of window-to-wall joints.

Moisture in a timber-based flat roof of cold deck construction

Reports tests made to examine moisture problems in a flat roof of cold deck construction. Tests simulated the effect of normal, wet and very wet conditions below the roof with no ventilation of the roof. Found that without ventilation there is a substantial risk of moisture degrade and condensation problems. Roof was then ventilated at five air changes per hour and this was found to be effective in solving moisture problems. Suggests this as a minimum ventilation rate and that where it is difficult to provide ventilation in a flat roof, a warm deck design should be considered.

A study of the wind forces on low rise building arrays and their application to natural ventilation design methods.

Due to the complicated flow phenomenon in urban areas, the assessment of wind pressure forces as well as the rates of natural ventilation for groups of low rise buildings is complex. As a result, the current design methods for the prediction of these forces are oversimplified and lead to inaccurate estimates of wind forces and ventilation rates in buildings. A survey of previous studies regarding wind properties and their influence on pressure forces along with work related to natural ventilation, wind loading and air flow round buildings was carried out.

Thermography. Testing of the thermal insulation and airtightness of buildings.

Discusses in general terms energy consumption and energy requirements and the testing and checking of buildings. Gives principles of thermography and discusses the influence of various parameters on the thermography of buildings. Gives rules for interpretation of thermograms and use of comparative thermograms. Gives examples of comparative thermograms for common defects in insulation and airtightness, and actual cases where certain constructions and components were examined. Shows effectiveness of improvements made to remedy certain types of defects in insulation and air tightness.

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