Framing Dormers

As you are probably well aware the easiest and most cost effective way of increasing the space available in the roof is to add a box or full width dormer to the rear of the property.

And on this page we will not only look at the process of adding the dormer framing but also the sheathing which is essential for weather proofing the structure.

For an in-depth look at constructing the fame check out our dormer construction page.

But essentially the process of dormer framing involves spacing vertical timber studs 350-400mm apart and topping them with a double thickness head beam and footing the structure with a horizontal base plate fixed to a steel beam or sometimes the new loft floor itself.

Strength is added to the dormer with the addition of a row of noggins before the whole unit is dropped into the previously created space in the roof but there is still plenty to do before the final cladding can be applied.

Once the dormer framing has been finished it must be weather proofed with sheathing as quickly as possible.

The purpose of dormer sheathing is twofold.

Firstly it serves as a background on which to put on the insulation for the dormer but it main purpose is provide the weather proofing for the structure.

The dormer sheathing is made from exterior grade plywood that is attached to the vertical studs of the framework. The next step is to cover the plywood sheathing with a breather membrane which allows condensation to escape from the new loft room.

The membrane is held in place by tacks and then overlaid with a timber framework on which the external tiles or cladding is hung.

Loft Conversion Ideas

Loft Conversion Prices

Adding A Dormer

Skylight Windows

DIY Loft Conversion

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