Tiny 1920's semi small scale loft conversion

[LKM]

Hi

We have a small 2 bed 1920's semi. When we bought it 7 years ago we did not plan on staying here to raise a family. However we now need more space and are reluctant to move as we love the street and also due to the face that we bought at the peak of house prices, there is little equity in the house.

Anyway we have decided to look at a loft conversion to add an extra (small!) bedroom. 2 houses in our road have had fairy extensive dormer conversions done but they are ugly and will cost us too much. The roof slopes on 3 sides - which I believe is called a hip roof)

We don't want to spend a fortune as we also want to add a small extension or conservatory onto the kitchen next year and are worried that the outlay might not be worth it in terms of the value it adds to the house.

My dad is a very competent DIYer, he has his own restoration business but has never done a loft conversion (although worked a long time ago installing dormer windows) and isn't familiar with planning/building regs. So it is up to me (a microbiologist = total building novice) to sort out that side of it!

I have done some research and think we should be fine to do this ourselves (well my dad and his electrician and joiner friends). I know I need to get someone in to draw up plans so that I can submit to the council - but who?? An architect, civil engineer??? What is the difference?

I was thinking of a velux window on the front of the house and a medium sized dormer window (not a big dormer conversion) on the back of the house above where i think the stairs would go up to create extra head space as you come up the stairs.

Couple of questions:
- I know we will probably need the floor strengthening but if just installing a dormer window and not a dormer extension would you also need the roof strengthened?
- I have seen prefabricated fibreglass dormer windows which don't seem to be very common. Is this because they are expensive or because they are rubbish?
- I know we need 30 mins fire proofing on the doors and on the stairs going up to the loft room and wired in smoke alarms through the house but apart from this is there anything else major to consider?
- What needs to be included in the plans I get drawn up for submission to the council. I don't think I need planning permission but do I opt for full plans submission or just submit a building notice. I'm a very by the book person so will want to do everything correctly but worry that submitting full plans and having various stages inspected will slow the project immensely. I want to have it done for Christmas.


Sorry for the long winded intro, hope someone can help me.

 

[OwainDIYer]

- I know we need 30 mins fire proofing on the doors and on the stairs going up to the loft room and wired in smoke alarms through the house but apart from this is there anything else major to consider?

If you can't get a loo up there as well, someone is going to have to go downstairs in the middle of the night. And when you do come to sell, a bedroom without a loo on the same floor will be less attractive to buyers.

Also you may have water tanks in the loft - are you going to be able to relocate those or have to go to an unvented heating/hot water system?

 

[tony1851]

You will need to put in new joists to form a separate floor; a dormer window can be added without too much messing about with the existing roof, though you will need to beef up the rafters either side of the dormer.

Are any purlins in the way, or are you working between them? The dormer could possibly be supported off one if it's not too high.

Getting suitable headroom over the stairs might be a problem - you might find one of the purlins is in the way.

If it's only a two-bed semi with a hipped roof, remember that your room won't be overly large.

Don't whatever you do get an architect involved - a local technician would probably be far more effective in getting building regs plans drawn up and passed.

 

[freddiemercurystwin]

You will probably need to strengthen the rafters as converting lofts often involves removing various existing structural elements and these need to be allowed for elsewhere, there will also be additional loadings on the existing rafters which are most likely undersized.

Whilst I have never used pre-fab dormers, I suspect they are expensive and poorly made.

The biggest headache in small houses is fitting a new stair access in and the headroom both for the stair up into the loft and usable headroom within the converted loft as valuable space at floor and roof level will be eaten up by additional structure. If you have an existing open plan layout on the ground floor this can be problematic with respect to fire escape.

You don’t need an architect or a civil engineer, you need an architectural technician.

If you are DIYing then a Full Plans Application is prudent, this will ensure you know what to do throughout the build and don’t have to make it up as you go along. As a self-builder I would be looking for a good set of plans, a detailed section or two and some proper details of the various junctions like how the floor is supported off the new steels, how is the dormer constructed etc etc.

Loft conversion Procedure goes something like this:

1. Unless you're willing to mess about with the layout on paper and learn about the relevant Regs then approach an Architectural Technician (see Yell or speak with friends or family for recommendation’s) not an Architect. No need to bother with a SE just yet though they will be required later on. Invite 3 Arch tech's round to have a look and give you a quote go with the one you think is best. You can also check out your Local Authority online planning register to see who the popular technicians are.
2. They will have a look and give you your free hour or so and hopefully give a rough idea that installing a staircase is feasible or not (presumably as similar houses to you have done lofty’s it will be. Explain you are a self-builder and you want a proper set of working drawings and not just a plan and generic section with a load of notes. Ask to see a typical loft conversion set of working drawings when he pops along to see you.
3. If it is feasible then give you a quote (probably somewhere around £500-800) and confirm to you how much the local authority fee will be (probably around £500) and how much the structural engineers fees would be (probably around £100-400).
4. If you are happy with his quote he will then do a survey.
5. Then he will produce some existing plans and a section or two.
6. Then he will produce some proposed floor plans showing you a workable layout or two (assuming a workable layout can be found). He should include a rough section to show how much usable headroom you will have. He should take into account the additional structure and insulation required.
7. Then if you are happy he will do the detailed drawings, including a couple of details showing the important junctions and at this stage he will be talking with a structural engineer to confirm steel beam sizes etc.
8. Then he should send you the completed drawings ready for your approval.
9. Then he submits them to building control for approval.
10. Then you can start work using his drawings.