Vaulted Ceiling

[PaddyP]

Hi there

I hope you are all keeping well.

I am currently looking the roof design of our house. We are trying to achieve a vaulted ceiling in the open plan area. This area measure 5m wide x 12m long. We are trying to achieve a full height pointed apex and on the ceiling and not have a flat piece at the top. 

The picture below shows the finish we are trying to achieve.

However, most people appear to have a flat bit at the apex rather than a point. In many cases this is to hide MVHR pipes. We will also have MVHR in the build so wondering is there an alternative? How can we achieve full height apex ceiling and still have space for services? 

 

Some options I have come across are scissors trusses and  parallel chord trusses. Are these viable options or am I barking up the wrong tree? Any opinions links, pictures etc are greatly appreciated!

 

 

[Russell griffiths]

same as MBC do their roof, just use metal web joists, run your large service mvhr pipes through the Webb’s, then install a vapour barrier underneath, then add a 25-35mm batten for small services, light cables and such. 

Insulation will be blown in cellulose stuff. Or warm roof on top. 

Not hard just needs planning. 

[PeterW]

At 12m long, that roof is going to need either some  serious steelwork at the apex to support the ridge, or you’re going to need to have something on show unless you use a scissor truss. 
 

I would start with a discussion with your SEng and then get them to give you options - that is going to need some serious design work to make it look how you want. 
 

[Ralph]

We had the same issue, we did not realise there was a flat piece until it was up. It was to accommodate the steal. What we ended up doing is using it for lights.
 
It does not bother me but it bugs my wife.

 

Edited February 2, 2022 by Ralph

[Ajn]

31 minutes ago, Ralph said:

It does not bother me but it bugs my wife.

Yes but it will still give you a pain in the neck even though you are not looking up at it.

 

[PaddyP]

5 hours ago, Russell griffiths said:

same as MBC do their roof, just use metal web joists, run your large service mvhr pipes through the Webb’s, then install a vapour barrier underneath, then add a 25-35mm batten for small services, light cables and such. 

Insulation will be blown in cellulose stuff. Or warm roof on top. 

Not hard just needs planning. 

 

Hi Russell, thank you very much for your feedback. That sounds like an excellent option using the Web joists. Does it need to be sheeted in OSB on the outside or just a felt? It will be a slated roof. 

 

5 hours ago, PeterW said:

At 12m long, that roof is going to need either some  serious steelwork at the apex to support the ridge, or you’re going to need to have something on show unless you use a scissor truss. 
 

I would start with a discussion with your SEng and then get them to give you options - that is going to need some serious design work to make it look how you want. 
 

Hi Peter, I have just received planning so just trying to get an idea of things in my head. I will definitely have a structural engineer on board. The scissors truss looks a good option. 

 

Hi @Ralph that looks a great space. From your picture it is difficult to see the flat piece at all. 

[JamesP]

I had similar issues trying to avoid a large steel ridge and MVHR pipe work.

I decided on building a curve using birch plywood.

 

 

[Ralph]

37 minutes ago, PaddyP said:

Hi @Ralph that looks a great space. From your picture it is difficult to see the flat piece at all.

Thanks, like a lot of things when building a house it seemed like a big issue and a compromise at the time but it pales into insignificance with all the other stuff you end up dealing with.

[JohnMo]

We have a flat section at the apex, but it's painted white, there are no lights pointing at the apex, so you just don't notice what up there.  The big windows at the front grab the attention.

 

Long spans equal either structural steel or glulam beams.  Our glulam beam are 450mm deep.  So even with 350mm insulation, you still end up with a small flat spot.

 

We are Scotland and the outside is covered in sarking board, breather membrane, then slates.

[Annker]

@JamesP That ceiling looks well done.

How did they get on with bending the ply to the curve that cant have been easy, did you use flexi-ply? 

[Chanmenie]

15 hours ago, Ralph said:

We had the same issue, we did not realise there was a flat piece until it was up. It was to accommodate the steal. What we ended up doing is using it for lights.
 
It does not bother me but it bugs my wife.

 

 

loving the minimalistic hand rails   ?

 

[JamesP]

1 hour ago, Annker said:

@JamesP That ceiling looks well done.

How did they get on with bending the ply to the curve that cant have been easy, did you use flexi-ply? 

I made a frame similar to a skateboard half pipe on the ceiling then fitted a layer of red faced ply followed by glued and pinned 4mm birch ply, it was a challenge.

I have built most of the house myself excluding electrics and skimming.

 

[freshy]

@JamesP Very impressive!

[Ralph]

1 hour ago, Chanmenie said:

loving the minimalistic hand rails   ?

We thought they were a bit to fussy so got rid of them all together. I do like our fancy stair balustrade though.

[SimonD]

20 hours ago, PaddyP said:

We are trying to achieve a full height pointed apex and on the ceiling and not have a flat piece at the top.

 

In a previous project, I had a SE, my father in law actually, who spent most of his life designing large steel and concrete buildings, design a steel frame for this. He designed some steel trusses that were tied at the ridge, negating any need for ties anywhere else, so left the whole space open. This solution also got rid of the need for a large ridge beam. In our case we had one large central truss and two smaller ones at each end of the building supporting smaller steel purlins, and cross braced (to provide racking strength) with small steels in tension on a diagonal from ridge to bottom corner.

 

The span was about 7m compared to your 5m and for the length you could just add several steel trusses.

 

Edited February 3, 2022 by SimonD

[Chanmenie]

10 minutes ago, Ralph said:

We thought they were a bit to fussy so got rid of them all together. I do like our fancy stair balustrade though.

 

Yeah thats fancy ?

On a serious note  looks a nice build ?

[Annker]

@JamesP Well done. I'm a carpenter myself and did a bit of curved work over the past year. Doing it to a high standard separates the men from the boys!

 

[Gone West]

On 02/02/2022 at 14:03, PaddyP said:

However, most people appear to have a flat bit at the apex rather than a point. In many cases this is to hide MVHR pipes. We will also have MVHR in the build so wondering is there an alternative? How can we achieve full height apex ceiling and still have space for services? 

Our last house was a portal timber I-beam framed house. Being a portal frame there were no internal structural walls and it was open to the apex wherever we wanted it. It was a PH and the MVHR vents upstairs were low level with the ducting running in the ground floor ceiling. I'm sorry I don't have any decent pictures of the ceilings.

 

 

 

[PaddyP]

@JamesP your ceiling looks fantastic! Love the exposed timber. Real attention to detail required there!

 

Hi @JohnMo thanks a million for those pictures. Great to see that the flat bit is barely noticable.

 

Thank you everyone for their help. I will speak with the structural engineer and see what they reckon. Has anyone used scissors trusses? While the flat bit is barely noticeable I still would like to avoid it if I can without too much additional cost and effort.