Rafter and purlin style roofs are usually found in properties built before the mid-1960s and they are absolutely ideal for those property owners who are looking to convert their loft.
This type of roof is exactly right as it has a steep pitch and lots of clear space between the timber framework.
As a very general rule of thumb the older the house the more roof space you are likely to have as in the past the tendency was to build houses with a much steeper pitched roof than is normal today.
The diagram below shows an internal view of a typical rafter and purlin style roof construction.
Headroom shouldn’t be an issue if the house has this kind of roof so it isn’t essential to include a dormer in your planned conversion.
Of course, you may wish to include a dormer in your design anyway – by doing so you will create even more room and broaden the scope of your loft conversion.
Loft conversions involving this kind of roof construction won’t ordinarily need planning permission as there will be no need to build above the existing roofline of the property.
Unless of course you do decide to also include a huge dormer.
The actual building of the loft conversion will be relatively straight forward as the room in the roof space and the way in which the roof is constructed allows for much easier building and greater flexibility in design and construction.
If your home does have this style of roof construction then you can plan your loft conversion knowing that just about anything is possible though your architect or builder will be able to advise you of all the many options that this kind of roof construction gives you.
For more info see the related pages below
Structural calculations for loft conversions are of course hugely important to ensure safety and that the proposed plans meet building regulations
What is the difference between planning permission and building regulations approval for loft conversions ?
Using And Fitting Loose Fill Insulation In Your Loft