Timber frame house and roof construction

[Abyaby]

Planning timber frame construction. Then, you can attach the interior ceiling above the rafter. But how should one think next? It should be a breathable house with walls insulated with hemp and lime. The roof insulation will be only loose hemp.
I'm considering a moisture barrier against the roof insulation. I'm also thinking about storms and how to secure the roof with insulation so it doesn't come off during storms.
I don't want visible bolts and neither do I want through-bolts that become thermal bridges.

 

[arkTecko]

You should probably explain your plans. Why do you want the ceiling on the outside of the framework? What purpose does the building serve? Will it be heated?

Mem post and beam is fun, what wood are you using? Do you have craftsmen? It sounds like you're designing it yourself, are you also building it yourself?

 

[Abyaby]

You'll probably need to talk about your plans. Why do you want the ceiling on the outside of the frame? What is the function of the building? Will it be heated?

Mem frame construction is fun, what wood are you using? Do you have a craftsman? It sounds like you're going to design it yourself, are you building it yourself too?

The frame, made of oak, will be visible on the inside, which is why the ceiling will be placed outside the frame.
It will be a residential house for year-round living.
I have a carpenter to help me, but I will also do some building myself. I now want to discuss and understand different roof solutions.

 

[arkTecko]

Difficult to solve a fully insulated roof, I think. You'll have to add rafters to the outside of the interior ceiling in that case, like 220x45? At least if it's going to be loose fill insulation. Polystyrene might work well for what you're after, but it sounds like that's absolutely not what you want. Maybe hemp-lime boards? What should the roofing material be?

You definitely need to draw sections so you can think about the eaves; I think that might be tricky to solve.

I would definitely use a vapor barrier between the interior ceiling and the insulation (or vapor retarder if you prefer). Even a breathable roof has difficulty handling condensation. Maybe you can have another airtight solution, like clay plaster? If you don't want a vapor barrier.

 

[Abyaby]

Difficult to solve a completely insulated roof like that, I think. You would have to build up on the outside of the inner ceiling in that case, like 220×45? At least if it is to be loose-fill insulation. Possibly Styrofoam would work well for what you're after, but it sounds like you absolutely don't want that. Maybe hemp lime boards? What should the roofing material be?

You definitely need to draw up sections so you can think about the eaves, I think that can be tricky to solve.

I would definitely use a vapor barrier between the inner ceiling and the insulation (or vapor barrier if you prefer). Even a breathing roof has difficulty handling condensation. Maybe you can have another airtight solution, like clay plaster? If you don't want a vapor barrier.

perhaps you need to think of "a roof on the roof" and then go according to tried and tested constructions.

 

[Charlotte Andersson]

When constructing a new building, an engineer should perform the necessary calculations and design solutions. This is not something a layman should be doing themselves.

 

[Biggle]

Planning a timber frame building. Then you can attach the interior ceiling above the rafter. But how should one think afterwards? It should be a breathable house, and the walls are to be insulated with hemp and lime. The roof insulation will only be loose hemp.
I am considering a moisture barrier against the roof insulation. I am also thinking about storms and how the roof with insulation should be fastened not to come off in storms.
I don't want visible bolts or through-bolts that become thermal bridges.

if you want visible rafters/beams, you must build an insulated roof above. Maybe, rafters, plasterboard/wood cladding, moisture barrier, subroofing, 20cm wood fiber insulation between studs, wind barrier, air gap, battens, roofing material?

To ensure the roof doesn't become too bulky, you can skip the insulation outside the walls and raise the outer walls by 20 cm. Gives the illusion of a thin, neat roof...

Tricky construction

 

[PeterFalun]

https://www.adlibris.com/se/bok/byg...t-hantverksmassigt-och-hallbart-9789189286825

 

[Abyaby]

if you want visible rafters/beams, you need to build on an insulated roof above. Maybe, rafters, plasterboard/wood cladding, moisture barrier, board sheathing, 20cm wood fiber insulation between studs, wind barrier, air gap, studs, roofing material?

To prevent the roof from becoming too bulky, you can skip the insulation outside the walls and there extend the exterior walls by 20 cm. Gives the illusion of a thin, sleek roof..

Tricky construction

That was very good advice. Thank you for that.