UPVC window measurements should be taken carefully. Before ordering new uPVC windows, it is important to accurately measure the height and width of the window opening. It is also important to check if the angles of the opening are all 90 degrees. If the new uPVC window is too small or too large for the existing window opening, this may harm its heat and sound insulation properties. The uPVC window construction may undergo unequal pressure and eventually fail. Even if you choose the best available uPVC windows but do not know how to measure windows correctly, their benefits cannot be fully enjoyed.
UPVC window measurements basic rules
It is the window measurements that should be entered in the price calculator. However, it is convenient to measure the window opening first and then subtract the width of gaps needed for insulation.
Height and width of the window opening have to be measured in three locations: height of the opening is measured on the left side, in the centre and on the right side; width of the opening is measured at the top, central part and at the bottom. This is done in case the window opening is warped.
It is important to determine whether the window opening is a rectangle (all the angles are 90 degrees). For this purpose you can use a spirit level or another tool. Alternatively, you can measure the two diagonals of the window opening and compare them. If the diagonals do not match, the window opening is not a rectangle and this must be marked in the draft.
Gaps between the uPVC window and window opening must be at least 15 mm wide on each of the four sides; this will be used for insulation.
uPVC window handing has to be clearly indicated in the draft. uPVC windows may be left-handed, right-handed, awning or tilting, or a combination of these. Depending on the selected uPVC window profile, there is a possibility to choose inward-opening and outward-opening uPVC windows.
It is also important to plan the following:
The method to be used when installing uPVC windows, whether it is drilling through the frame or using cleats to fix the uPVC window in the window opening.
Whether the project includes window sills or not.
The correct width of gaps between the uPVC window and window opening so that to insert insulating foam. This is calculated according to the selected installation technique and building requirements.
As was already mentioned, it is important to pay special attention to the size limitations of uPVC windows in order to prevent any future problems like difficult opening / closing, glass fracture or profile warping.
Following these rules you will have the correct measurements for uPVC windows which will prevent cold bridges, provide a sufficient sound insulation, remove any critical static load, prevent burglary attempts and stay the same for many years. Specific details of how to measure uPVC windows are given in the next section.
UPVC window measuring step by step
1. Measure the height and width of the aperture. Each dimension has to be measured three times: height is measured on the left side, in the centre and on the right side; width is measured at the top, central part and at the bottom. The smallest of the three measurements is registered.
2. Determine the size of uPVC windows that you need. Consider the width of gaps to be left around the perimeter (which will be used for inserting sealant) and note down the uPVC window measurements in millimetres.
3. Check whether the window opening is a rectangle (all angles have to be 90 degrees). You can use a spirit level or another tool. Alternatively, you can measure the two diagonals of the window opening and compare them.
4. Indicate the handing and opening direction of your chosen uPVC window (whether opening inwards or outwards). For example, you are looking from the inside of the room, uPVC window opens inwards and the handle is on the left. Use a solid line to indicate an inward-opening uPVC window (looking from the inside). Use a dotted line to indicate an outward-opening uPVC window (looking from the outside).
5. Tolerable inaccuracies. There are certain tolerable inaccuracies while taking measurements. Measurements of uPVC window aperture can be +-12 mm, while the total inaccuracy can be up to 24 mm. Measurements of uPVC windows can be +-2 mm, while the total inaccuracy can be up to 4 mm.