The location of windows in the masonry openings

Service Description

The location of windows in the masonry openings

An exterior wall has two equally important elements in a building structure, the elements of masonry framed by the resistance structure and the glass surfaces represented by the windows and doors.

If the wall has a significant thickness, 25cm, 30cm, 38cm, etc. at the masonry level, as we choose, the thickness of the window joinery is about 60-70 mm as is the quality of the used thermo-insulated joinery. Existing a difference in thickness between these two elements that make up the building envelope, it is mooted a question of positioning the window to the wall thickness. Depending on these possible positions of location, the conditions of the temperature of the window parts (interior and exterior) and the adjacent regions can vary. It is important that the temperature does not reach the dew point, which could lead to condensation on the analyzed surfaces or to mold on the wall which is adjacent to the window.

A quality insulation of the building envelope must be made correctly in the field of the wall especially in the areas where we have edges, seams, joints etc. It becomes more important the design and execution of these areas where the designer lines change their direction than a flat surface of a wall. A window is considered such a situation in terms of issues of placing and of the connection areas with the mansory opening must have a continuity of thermal insulation in the areas of junction between these elements.

Possible positions of the windows in relation to the masonry wall:

1. The exterior surface of the walls location

The justification for this positioning belongs to the necessity to get inside a larger space on the lintel area. The solution involves the disadvantage of poor circulation of the warm air currents resulted from the heat source (radiator). The lower part of the window will have a lower temperature which will promote the condensation appearance. Meanwhile, on the outside we will have a greater exposure of the window to the outside cold air, by the total exposure in the plan of the thermo-insulation will be more complicated to close the perimeter area of the window.

2. The inner surface of the walls location

Beside the previous case, this time the warm air currents from the inside will act on the entire surface of the window and the exterior surface will be protected from cold currents. The risk of condensation on the inner surface of the window is drastically reduced. However, the window plan will not have continuity with the thermal envelope of the wall, the window being placed on a thermal bridge between the outer surface and the inner side of the wall. This will lead to a high risk of condensation on the width of the influence band of the thermal bridge in the window perimeter.

Aligning of the window with the internal surface of the wall will lead to difficulties regarding the closing of the joint installation of joinery. On this area will be used only a thin layer of adhesive / polishing plaster coat. For this reason, the area will be permanently exposed to cracking. In addition, in the aesthetic plan it will not be the best option, it will immediately be seen the impact on the overall general glass area of the wall, creating a feeling of small space. The recommendation is not to align exactly to the inside surface of the wall, but to keep a minimum inside lintel, both for a higher aspect and also to finish the edge are of installation.

3. The thermal insulation plan of the wall location

It represents an acceptable solution of location of the window in the masonry opening, this being in continuation of thermal insulation plan. The more surface contact and thermal insulation of windows is higher, so avoid the thermal bridges, for obtaining a good insulation. In these cases the complications appear when you are installing the window, catching on the contour requiring specific mounting clips for lateral grip.

4. The middle of the wall location

Is the most used solution, both in new buildings and in existing ones that need upgrading. The location of the joinery in the resistance plane of the wall is done by taking of appropriate measures for thermal insulation of the exterior lintels, until the window plane. In these cases, depending on the size of the opening we must take into account the thickness applied on the exterior lintels, so as the window case to not be covered by it. Is the case of shell houses which are measured for the execution of the joinery.

Besides the location of the window in the wall thickness, it is important to perform a solid grip in the masonry opening, mandatory by mechanical fixing systems. Also, sizing the width of 2-3cm above the facade level and the enclosure into the thermo-insulation, ensuring the slope, the tightness of the exterior lintels on the joinery margin are details that can make a window correctly positioned to still produce problems to the inside and degradation of adjacent window areas.

House Extension and Refurbishment in London.

Loft Conversion and Refurbishment in London.

House Renovation and Refurbishment in London.

Office Refurbishment, Shop Refurbishment in London.

Bathroom and Kitchen Refurbishment in London.

House Refurbishment in London. New Build in London.

Flat Refurbishment in London. New Build in London.

Electricians and Plumbers in London. Refurbishment London.

Kitchen Furniture Fitting in London. Cleaning in London.