Loft Conversion - Yay or Nay? Advise please!

[bonn4lolly]

Hi All,

We recently moved into a new house. I'm slowly working my way through a list of DIY tasks the length of my arm. I'm up to the loft at the mo and would love to learn about the options open to us.

There is great height to the loft, but limited width owing to the roof frame. What I'd really like to know is whether the central joists could be replaced with something that would give us width, and make a loft conversion a realistic option. And if so, what would the likely cost be? The house was built ~1995.




My other question regards moving the loft ladders to the other loft hatch for easier access BUT a plank connecting the joists is in the way (nowhere for the ladders to slide back to). Does anyone know if it's safe to cut the red-marked section of plank out and reattach it further up, thus giving space for the ladders? It' doesn't seem to bearing any weight/pressure, but I'd rather not have my roof cave in...



Many, many thanks in advance for helping me out on this No-Know topic!

Andy

[b0redom]

Depending on planning permission you can. We had a loft conversion from something similar to yours. We were allowed to put a dormer on the back - almost squares off the back of the roof. The joists are replaced by steel strutts, and you'll need a RSJ to support it. In short it's not a DIY job, but we gained a massive double bedroom and ensuite (think approximately 3/4 the footprint of the house) for way less than the cost of moving - it still wasn't cheap mind.

Consult a builder and if you have any questions, feel free to drop me a PM.

[bonn4lolly]

Thanks b0redom - I guessed there would be at least one aspect we couldn't do ourselves (happy to do the plaster boarding etc). I think that even we had just the central joists replaced we would get 1/2 to 2/3's the footprint of the house.

Would you mind letting me know the rough cost of the heavy construction work (RSJ and steel struts), or if you don't know the breakdown then the total cost? You can PM me if you don't want to put costs on the forum.

Cheers,

Andy

[b0redom]

Well we had the lot done, with k-glass windows, fully fitted bathroom etc. Probably not much change from £35k fully decorated/thermal blackouts for the velux windows/planned/approved/new pumping for hot water/central heating etc.

Note you may need to change the doors on all floors and have proper wired in smoke alarms fitted etc (we did).

[Saracen]

My first bit of advice would be DO NOT start cutting chunks out of roof joists without expert advice. You could be letting yourself in for all sorts of problems. I'd also want it cleared by more than a local jobbing builder, but someone that understands roof design, stresses and loads.

Also, IIRC, when you talk about moving loft ladders, I seem to remember something about the nature of the conversion being important, for example, redesign to increase storage space was one thing, but if you're planning on living space up there, like bedrooms, bathroom, etc, then you get into another whole area of compliance with fire regulations (*), and IIRC, that requires stairs not ladders, and stairs that comply with fire regs at that .... unless, perhaps, there's an external fire exit from the loft rooms.

If I were you, I wouldn't even think of DIY on this, until you've checked out exactly what you can and can't do, and how you can and can't do it, or you could find yourself prosecuted for breaching regs, unable to get home insurance, and even not able to sell the house until you 'rectify' any non-compliance.

If you're planning on DIY, you may be able to do a lot of it yourself, but I'd strongly recommend expert opinion on what you do and how you do it.





(*) I looked into it a few years ago, but didn't go ahead for various reasons, not least, thinking of moving instead. I do remember several websites giving advice on building coxe co plyance, fir regs, pkanning permission, what is and isn't necessary. I just don't remember all the detail, or what the sites were.

[b0redom]

+1. Our builder (who came with lots of recommendations) engaged an architect to do all the above. Money WELL spent. Also local authority sign off is mandatory following this sort of building work. Make sure your builder knows the planner and how to get stuff through. I didn't realise you were planning on doing the structural stuff yourself.

Rereading, going up and down via a ladder isn't really viable if you want a proper room you can use on a regular basis. As Saracen points out fire escapes etc are also something which needs considering. You don't want to be trapped on effectively the 2nd story of a house when there's a ground floor fire with no way out.

[peterb]

m not a builder/architect/civil engineer, but...

Yes it could be done, and it would probably be cheaper than moving to a bigger house.

BUT - I doubt you could do the structural work yourself, although that depends on your skill

You would need an architect or structural/civil engineer to advise on the building

You might not need planning permission (check your local authority) unless you are raising the roof line, but you would need building control inspections

Given the age of the house, the ceiling joists are probably sufficiently thick - older houses tended to have thinner ceiling joists upstairs
(lower cost) because they carried less load than the main occupied levels, but if not, they might have to be replaced.

The roof looks a good height, but the roof rafters would ned substantial re-work. While that might not entail a complete re-rod - that could not be ruled out.

DON'T cut any roof supports at all! (Caveat - unless you put replacement supports in - and even then, I'd be very wary). Some timbers are put in as temporary supports during construction, and left in place, even though they are no longer load bearing. That timber might be something like that, but it needs examination on the spot - and even then it might not be obvious. It is almost impossible to be certain from one photograph, so advice has to be don't.

Anything on this scale does need professional advice, and almost certainly professional installation of the load bearing structures pretty much up to first fix. If you are a competent DiYer, you could probably do second fix work yourself.

[jimbouk]

RE: Loft ladder. We had a large hatch put in with a folding ladder attached to it. It's a bigger hole in the ceiling but doesn't take up any more space than the hatch size in the loft when folded up. This did involve cutting beams as out house had narrow beam gaps, hence I wasn't allowed to do it and a 'professional' was brought in.

[kudos1uk]

another option without making the hole bigger is a concertina ladder, that just sits in the opening without enlarging or cutting joist but does mean pending out on a new ladder, but it's simple DIY.

http://www.tesco.com/direct/30m-conc...r/421-5673.prd

[fuddam]

I did it myself, with help from a qualified builder. Point was that we didn't make it into a formally recognised room - as Saracen stated, there are so many regs esp around the permanent staircase/ firedoor etc, for which there wasn't space. Didn't move the struts, since was do-able but going to cost a whole heap. I had to make it usable within 2 weeks while my wife was away, lol.

New ceiling insulation, loft window installed, standing desk/s, plasterboarding etc

When we come to sell the place, will simply be a glorified loft, so not added REAL value, but turned it into my office. Made space. Cost was minimal.

[Repressor]

That bit you've marked red is taking all the lateral loading. It's basically stopping the roof trusses falling like dominoes.

[Funkstar]

That bit you've marked red is taking all the lateral loading. It's basically stopping the roof trusses falling like dominoes.

You are right. However, without consulting someone that know more and can see it in the flesh, it could be as peterB siggested, that they are now redundant.

[scaryjim]

As a couple of people have said, any work you wanted to do to create living space should be planned by a proper architect, and will need local authority sign off. When my mum turned her bungalow's loft into a huge living room the LA inspection decided that there wasn't enough clearance at the top of the stairs and a chunk of the floor had to be lowered to compensate. Any decent builder in your area should know an architect or two who can do the work - if any builder you speak to claims they can do it themselves walk away - if they're not charging you architects rates it probably means they haven't had the training to do it properly

One thing I will say is that it's going to cost you, and there's a reasonable chance it won't increase the value of the house by a commensurate amount when it comes to moving. Be prepared to spend the money just to get the house how you want it - if you're worried about getting the money back when you sell, it's probably not worth doing.

[b0redom]

...on that note, the guidance we got was that it will probably increase the value of the house by the outlay. So if you spend ~35k, it'll add ~35k to the value of the house. Not really a concern for us as we are not planning on moving. Of course this is in SW London, so YMMV

[ik9000]

mate, where are you based?

In case you are short of time the short answer to all your queries is NO.

the medium answer is you appear to have a bespoke timber trussed rafter roof, the red member is probably for lateral stability bracing, though it is difficult to say for certain from localised photographs. While it may not have primary load bearing function, stability is equally important and I would NOT advise its removal without seeking professional advice from a structural engineer. As someone else has pointed out, it is the stability bracing that stops the thing raking over sidewards like a proverbial house of cards/dominoes etc

The long answer is:

Modifying trusses can be done, but needs specialist consideration - ie. a structural engineer to review the proposed alterations and ensure strength, stability and stiffness are maintained.

If it were my house get new timber rafters and hip, ridge, ceiling and eaves beams installed to create a fully open space. Where the external profile and appearance matches the existing no planning permission should be required provided the space remains for infrequent access loft storage. (The space inside your loft is usable already, albeit jolly inconvenient). Building control approval would be required.

Where you intend to make it into habitable rooms however, and adding windows etc you will find you will need both planning permission and building control approval, for which you will need architects and structural engineer's drawings and documentation (calculations etc).

If you really have the money go for a new mansard roof to maximise area (subject to planning consent).

Note that conversion of a loft to habitable room in a 2 storey house to 3 storey house conversion requires installation of straps and ties to comply with Part A of the Building Regulations (robustness to avoid disproportionate collapse) and this will need a structural engineer's design approval by Building Control. There will also be architectural aspects, such as the need to comply with part E acoustics, part L thermals, part M and N (Access and lifetime use stuff), part B fire regs, and all the other joyous fun that comprises the (legally compulsory) Building Regulations.

Builders are great, and try to be helpful but I have seen too many cases of helpful mr builder not having much of a clue about the full implications of their advice and actions. Not all can be labelled that way, but the best way to avoid unnecessary risk and legal ramifications to yourself is get professional advice. A couple of hours of £75 per hour time fee for an architect and engineer could save you literally thousands if stuff goes wrong cos your builder thought it would be ok, but the council (and law) says otherwise

a very good site is findanengineer.com which will help you find chartered structural engineers in your area.

edit: any beams bearing onto/alterations required to party/shared boundary walls will need approval under the Party Wall Act and you will need to get Party Wall Award with relevant parties, employing a Party Wall Surveyor to do so.

[ik9000]

on costs.

Timber is cheapest - take a look at Wickes etc to see how cheap. Carpentry time, and all the galvanised or stainless steel straps and ties are where the expense comes in.
Steel expensive. Prices vary probably looking at ballpark £2k per tonne for members of the size for domestic use (typically 30-60kg/m though it depends on spans and loadings), with installation etc on top. Prices are so volatile at the moment it's hard to give useful advice. You'd want a QS (quantity surveyor) or better still a steel supplier/fabricator to advise you, though builders will add a mark-up so it's a complete minefield. And do not forget the hassle of handling such heavy beams into position - not a DIY job for the inexperienced.
Clad roof timbers in WPB plywood 2 layers say 12mm thick.
Then you have the finishes to go over the top. Tiles etc and lead flashings.
Somewhere in all of that you have to incorporate insulation either the ceiling or the roof itself. and coordinated ventilation strategy, damp-proofing, etc. There's a lot to get right, and it's easy to get something wrong and have damp problems or worse for years to come.

Internally, you might be able to get away with keeping existing ceiling but it would probably be easiest to have all ceiling removed and new one put back. You'd get more usable space too.