Vaulted ceiling in barn

[Frank & Rosie]

We are converting a stone barn with a clay tile roof in Department 24. The roof needs to be stripped and the timbers overhauled and repaired and where necessary replaced. We want to have a vaulted ceiling so that the rafters are visible from inside (underneath). We are looking to find the best method of insulation bearing in mind the limited space, also a way to finish in between the rafters internally. Has anyone any suggestions? We were thinking of the multi layered foil type insulation - Has anyone experience of this? Regarding the internal finish, it would seem (looking a pictures in magazine and books) that most appear to be finished with plasterboard in between the rafters, our architect suggested white poplar tongue and groove applied above the rafters - please, any help or suggestions gratefully received!

[cooperlola]

We had the foil insulation put up in between the rafters and the tiles  - this by professional roofers.  If you do likewise you can then put plasterboard or t&g as you like.  Personally, I don't like the effect of t&g (this is what the previous owner had done downstairs) - prefer the smoother plasterboard finish.  I'll try to take a pic' or two for you.

[Frank & Rosie]

Thanks for your reply, I think I would prefer the plasterboard finish too but a bit worried about the timbers getting marked and smeared by the plaster skim finish. Would love to see a pic.

[cooperlola]

Here is what the t&g looks like, F&R

[IMG]http://i134.photobucket.com/albums/q103/cooperlola/ceilingshome002.jpg[/IMG]

And here is the "foil behind the beams" bit

[IMG]http://i134.photobucket.com/albums/q103/cooperlola/ceilingshome005.jpg[/IMG]

This is on  a new roof but the insulation was put on from the outside after the roof structure was on but before batons and tiles.

[Wozza]

If you are re-roofing you can put the foil on the outside (above) the voliges - I have been advised that if you use poplar, then make sure there is plenty of ventilation, as it is like a sponge for soaking up moisture. I think that if you use chestnut voliges you can put the membrane then insulation directly on the boards and leave an air gap above for insulation. The plus side of the sawn chestnut voliges is that they look quite nice from underneath - not as clinical as tounge and groove, quite authentic (although truly authentic voliges are not straight edged and butted together).

I think poplaris about €6 per sq.m, whereas chestnut is about €9, but well worth it - we have both and the poplar is getting covered.

[mark24]

If you are taking the existing roof off ,Just fix plaster board with insulation on the back to the out side face of the rafters .Then  counter batten vertically ,felt with a breather membrane and batten for the tiles horizontally .

Then inside all you will have to do is fill a few joints in the plaster board .

[Frank & Rosie]

Thank you very much for your reply and the pics.

[Frank & Rosie]

Thanks Wozza and everyone for your replies. What are Voliges? Do I take it they are just sawn planks? It is very interesting to hear your comments on White Poplar versus Chestnut. If voliges are not tongue and groove, does the wood shrink at all leaving gaps? Have you had any problems with twisting, warping and shrinking? At present, we are still trying to get as much information as possible. We still haven't decided whether to go with wood or plasterboard. I believe wood would be easier to use but it would be prone to insect attack and would need to be treated which could also darken the wood. Plasterboard would give a lighter and possibly more pleasing finish between the rafters. Then of course, there is still the matter of the insulation. I believe you can get plasterboard in France with insulation already bonded to it otherwise we are still very much drawn to the multi-layer foil insulation. By the way, we are intending to use re-claimed flat clay tiles (hopefully re-using 70 percent of what is already on the barn). Any further info greatly appreciated.

[Frank & Rosie]

Mark, I must admit the plasterboard with the insulation on the back of it does sound a great idea. Do you have any experience of it? Is the insulation effective? Does the plasterboard not crush? Do you know who stocks it?

[Wozza]

Voliges are the wood planks used to board roofs in France. Poplar does I believe tend to shrink and warp easily, hence why it may have been suggested tounge and groove, although I used some recently without T&G and it still seems OK, but I did fix it down well. Our main house is boarded with chestnut, again sawn, not T&G and looks great. It does tend to shrink a bit, leaving gaps, but there is a black membrane above, so all gaps are black. The silver insulation stuff is above that.

You can get the polystyrene backed plasterboard at any Brico, poly thickness from 20 to 80mm I think, but I'm not sure if it is good enough an insulator for a roof - I think it is intended for providing insulation to walls.

Warren

[mark24]

The only form of insulation we have is 25mm hard board  witch has a bitumen coating on the out side face .This is on the back of the voliges .

[IMG]http://i134.photobucket.com/albums/q94/shanfjr/DSCN05200001.jpg[/IMG]

 

We live in two barns have a look http://www.french-property.com/vp/nv/id/42417/vi/all

It was converted 30 years ago buy others before us

The living room is 70 squire meters and all we have is a old 10kw godin heater at one end that keeps the room at 19c/21c most of the time when it gets bellow -3c we light the big fire or just top the heat up with a 3kw petrol heater .

 

(Do I have any experience of it?) Yes about 30 years worth

(Is the isolation effective?) Yes if fitted correctly

(does the plaster board not get crushed ?) Not if your careful and  its done correctly

 

Use screws or heli fixings for the counter battens then fix a breather membrane then the roofing battens .

I always use nail guns for fixing the battens as this does not make the repeated vibrations that a hammer makes