Stable conversion and tons of compromise

[Jilly]

 

 

Hi, there is a risk I won't sleep after getting all your opinions, but I've had a full plans BC application done and a second structural engineer has said that we don't need to underpin as the loadings on the existing slab are the same, so I want assurance that it complies and to let me chose a builder.  

 

The project is a headache because it is small (60m x 10m) and putting internal wall  insulation would reduce the floorspace to about 48m2, so I've opted for exterior, under the featherboard, but there is very little space and my wall u values look rubbish.

 

The existing roof trusses preclude any way to create a vaulted ceiling and so the roof would have to come off (heartbreaking, its perfectly good!) to do this. This might give an opportunity to create an extra bit of overhang to get more insulation in.

 

Lack of headroom is the reason for the poor floor insulation. 

 

I was thinking of boarding the ceiling because it is quick,  cheap and would allow a lot of insulation, but my architect technician says it might be like a hobbit house... (2.1m height)

 

Would a vaulted ceiling be considerable more beautiful/saleable/luxurious?? 

 

In view of reading Jeremy's post on u values, I've maybe just talked myself into removing the entire roof to solve a few problems...

Prelim BC.pdf

Edited May 1, 2020 by Jilly

[ProDave]

To be frank, I would now be going back to planning to get something larger than the existing building, arguing you should be able to enlarge it by at least PD limits.  And then be looking at a rebuild which has the VAT benefits and will get you the building you really want.

 

I am sure you can re use a lot like re use the roof tiles, the cladding etc.

[Jilly]

No, I've tried, they are very clear, the house has to be habitable and then I can apply for an extension as a householder. It's a conservation area and all my PD rights have been removed, cant even have a chimney!

[Russell griffiths]

Will they let you increase the ridge height, to gain more internal height. 

[Jilly]

Maybe...

[Onoff]

14 hours ago, Jilly said:

60m x 10m

 

6m x 10m surely?

[Onoff]

That truss roof came as a kit. Take it apart carefully and sell on.

[Russell griffiths]

37 minutes ago, Jilly said:

Maybe...

Well that maybe is what you need, if you are taking the roof off it needs to go back on at 2.4 minimum and then re make a couple of vaulted areas over the lounge, diner. 

Do you need that dividing wall between kitchen lounge? 

I take it its  a wall I cannot enlarge the drawing on my I pad. 

 

Do you have a budget?

i think your measurements are a bit out for internal insulation you say it would drop to 48m I think that’s wrong, you would lose 165mm on both walls so taking your internal to 10 x 5.6 roughly so ending up with 56 hope I haven’t miss read that. 

 

 

[Jilly]

5 hours ago, Onoff said:

 

6m x 10m surely?

Yes, sorry!

 

[Jilly]

5 hours ago, Russell griffiths said:

Well that maybe is what you need, if you are taking the roof off it needs to go back on at 2.4 minimum and then re make a couple of vaulted areas over the lounge, diner. 

Do you need that dividing wall between kitchen lounge? 

I take it its  a wall I cannot enlarge the drawing on my I pad. 

 

Do you have a budget?

i think your measurements are a bit out for internal insulation you say it would drop to 48m I think that’s wrong, you would lose 165mm on both walls so taking your internal to 10 x 5.6 roughly so ending up with 56 hope I haven’t miss read that. 

 

 

I think you are looking at a stable wall that's being demolished.

 

Yes, I was going to compromise by vaulted over the kitchen diner, as shown. 

 

Re the loss of internal space, the architect did the calc, but i'd specific sweeps wool, so maybe that's why it seems a big loss of floor space? Better check...

[JFDIY]

What work needs to be done to the roof to bring it up to regs? Looks like there is no membrane under the lower part one side.

 

If there is a few bits to rectify you may find that new raised collar trusses would not be that expensive.

 

You could do just the half over the kitchen/dining area.

Or go for fully vaulted in that area and raised collar trusses in the bedroom.

 

I think without doing something you take away the appeal of a barn; most people will expect a bit of a feature and spending a few £k here will make all the difference.

 

I take it there is no option to lower the floors?

 

 

[Jilly]

We could lower the floors, but if we do that we have to underpin...

Edited May 3, 2020 by Jilly

[Russell griffiths]

What is your wall make up currently, it would be good to get an idea on how to get some insulation in there, I would definitely talk to the council regarding lifting the roof higher 300 mm will make a tremendous difference. 

A budget would be handy, I do believe you mentioned it is fairly small, but that is cool need to know how to get the best bang for your buck, it would be horrible doing all this work to end up with something you don’t really like. 

[PeterW]

Ok so 6x10 is pretty small so let’s go from there. 
 

To strip the roof retaining the tiles will be about £1500 assuming you’ve got scaffold already. 
 

New Collar trusses at 400 centres (26 of them) would be no more than £100 each. Fitting would be about £1000 all in once you factor in a new wall plate. 
 

Re-roof should be about £35/sqm inc breather membrane and battens, measured flat. £2500

 

So that is about £7,500 to re-roof it. Using a collar truss means you only need to use PIR in the sloping cheeks, the rest can be cheap loft roll. I wouldn’t go more than 2600mm with the collar (ie 500mm higher than now) as otherwise it will start to feel like a church and be a bugger to keep warm. 120mm PIR in the cheeks, 400mm fibre on the flat sections, vapour membrane and then board and skim. 
 

You could also “fake” the beams with an overlay on every other rafter with something like a rough sawn oak 4x2 to give you a rustic feel but that’s up to you. 
 

Floors - straight over the top (assuming it’s “flat” with 25mm of EPS75 polystyrene, DPC then 100mm of PIR. 22mm Caberdeck laid as a floating floor glued at all joints. 
 

Walls - bin the sheep’s wool as it’s appalling for uValue and is for people who can afford to lose space, you can’t. Get the builder to site build some 140mm thick stud walls, line the backs with 9mm OSB and then lift into place, leave a 25mm gap to the bricks. Fill them with 140mm Frametherm 35, Vapour barrier then board and skim. 
 

Internal walls - build them off a double sole plate of 6x2 sat on DPC on the floor so you have a solid base, shot fired steel brackets either side if you want it really solid. 
 

Will they allow you any conservation roof lights or similar ..? 
 

 

 

 

 

[Jilly]

No roof lights, but can  apply after its habitable. The walls are 140mm block with featherboard cladding. 

Edited May 3, 2020 by Jilly