Attic construction, dormer bungalow

9 Feb 2007
Reaction score
United Kingdom
We have a 1970/71 'ish dormer bungalow style semi (with the flat roof's now pitched)

The attic space inside the main roof area (the pitches over the original dormer flat roofs are not accessible) is only small, approx 6 foot head height immediately below the bridge board.

The purlins are 8.75" x 3" and extend into the brickwork. Joists are 5" x 2" (approx 47cm between centres). The roof rafters extend down over and are knocked to sit on and are nailed to the purlins and continue down the pitch of the roof and are nailed to the joists. Below the purlins are two further horizontal support beams that are fixed to the purlins via vertical and heafty diagonal supports.

- other end is roughly mirror image.

Now, since the house is constructed as a dormer style, the front and rear upstairs walls are not brick but a seeming double plasterboard, batten, vertical tile affair. The external side wall does extend up the full height of the dormer and is brick as is the party wall between the two. Since there is effectively no brick structure front nor back and the roof originally (and still does under the added pitches) extends into a flat roof over the dormers, do the attic joists sit on anything of any real structure (no wall plates?) or are they totally supported via the roof structure, i.e. their ends being attached to the roof rafters (which are in turn supported on the purlins) and also by the horizontal supports beneath the purlins (these are roughly nailed through into each joist passing beneath).

I've boarded it up there with T&G floor panels but I'd like to better know the construction style.

Thanks all...
Sponsored Links
Looking at the second image, is the floor of the attic also the ceiling to the dormer?
If what i have said is correct, then it is likely that the attic joists sit on the timber dormer walls that in turn sit upon the internal walls of the house.

There may be some kind of king beam running along the heads of the dormers that will support the attic joists/dormer ceiling and be adequately supported by the timber dormer walls.

All the weight will ultimately be transferred down to the inner skin walls at the ground floor.
Sponsored Links
Thanks for the replies. Yep, the attic joists extend out to where they join the roof rafters - which is where the original pitch ends and the flat roof of the dormer begins (underneath the subsequent additional pitch) - and continue out as the construction of the flat roof I assume.

Certainly, the ceilings of the rooms below the dormers and below the open attic area are all at the same level so I assume they are attached to the same joists. As said, only the front face of the dormers are of frame construction, both side walls are solid brick all the way to the front although externally finished with hanging tiles the same as the front.
In the first pic at the top of this page, how much did it cost to put the sloping tiles on the flat roof.

many thanks

Think it was around £250 per side, i.e. £500 front and back. That was around 14 years ago for ours though.

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local