The following guide will describe four ways of fitting your retractable awning on your house: Fitting on vertical wall, fitting on horizontal eaves, fitting under roof rafters and fitting in extension of roof rafters. The choice of fitting method is often determined by the desired height of your awning.
Brief Introduction to Awning Fitting
Fitting of awnings is essential for the stability of the awning. The reason for the fitting being crucial, is that this is the weakest link in the strength of the awning, because it is what binds awning and foundation together. For a wind class III awning, the fitting will break before the awning itself, in case of strong wind.
Number of Necessary Mountings
The number of necessary mountings for an awning highly depends on the quality of the awning. As a rule of thumb, one mounting is needed for every arm on the awning. Awnings up to approximately 6,5 meters usually have two arms, needing two mountings, whereas lengths from 6,5 to 8 meters usually have three arms needing 3 mountings.
Where on an Awning to put the Mountings
It is important that the mountings are fitted on the awning, close th where the retractable arms are mounted in the awning cassette. This provides the optimal transfer of the force on the awning to the wall (or rafters or roof), on which the awning is fitted.
Some awnings have movable arms. This gives an ability to move the arms, so that they correspond to where it is desired to put the mountings. This is relevant in the case of rafter fitting, where the location of the mountings is determined by the location of the roof rafters. In this case it is best if the arms are moved so they are in front of the rafters, again to render possible high force transfer from awning to rafters.
Awning Fitting on Vertical Wall
This is the standard fitting of an awning, and also the least troublesome. The only demand here is that the wall is stable enough to carry the awning. A simple test of the quality of the wall is to pound on the wall with a hammer, and note if the joints are falling out. If they are, this is a big indicator that the wall is not fit for carrying an awning. For newer houses this should however not be a problem.
Typically it is desirable to place the awning 2,5 - 2,6 meters (8.2 feet - 8,5 feet) above ground level. The reason is that an awning typically will have a drop of 12 degrees, resulting in a drop of approximately 60 cm (2,0 feet). This results in the front bare of the awning being in a height of approximately 6.6 feet, so that the front bare does not bother when being under the awning
Awning Fitting on Horizontal Roof (Eaves)
This kind of fitting under roof/eaves is a good solution, provided that a stable eaves is present. When fitting this way, remember to order the specialized eaves-mountings. They have to fit the normal (wall) mountings, that comes with the awning. When fitting in this way, the eaves should be at least 2,6 meters (8,5 feet) above the ground.
Awning Fitting on Under Roof Rafters
This method is to fit an awning under roof rafters. The advantage of this fitting method, is that mountings for this kind of fitting usually can be ordered with the awning for a good price. The critical point is, that fitting under roof rafters demands the rafters begin very robust and at least 10 cm thick (4 in). Since an awning usually comes with only two mountings, the fitting area on the rafters is relatively small, which always is undesired. However the solution is possible and results in a discrete awning fitting, just make sure the quality of the rafters.
Awning Fitting in Front of Roof Rafters
This method is the most troublesome, but a very common and good solution. Here the awning is mounted in front of the eaves, fitted on the roof rafters. The reason that this is a common way of fitting an awning is that the awning in this way is placed higher, than when the awning is under the roof rafters. This is desirable if the height of the eaves is less than 2,6 meters. Also it can be desirable, if fitting the awning on the wall or under the roof rafters, makes the awning be in the way of e.g. a terrace door.
Usually the way this is done, is that a professional awning fitter measures the slope of your rafters. Also he must notice the design of the awning wall mountings, delivered with the awning. With this information, the awning fitter can produce a specialized roof rafter fitting, that matches both awning mountings and your rafters. This specialized roof rafter is typically 80 cm long (32 in), such that the fitting area between rafter and fitting is very large.
Benjamin Biegel
Awning Expert
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