Any structural engineers / timber frame specialists which can help?

[azmontana]

Hi All,

Been a while since I was on here. Last garage I built was a 3 car garage in the UK. It was made from brick. Build thread is on here

I'm looking to build a new garage but to keep costs down want to this out of timber. Size will be 8m x 4m x 2.4 eaves and then a pitched roof with a height of 1.5m.

As I want to fit a lift in the garage I'm wanting an open span roof. I wanted to know what size timber should the ridge board be. I'll definitely be using C24 but unsure on size or whether I can get something which will span 8m?

For the rafters I believe 150x47 mm C24 should be fine as the lengths will be 2.5m.

Also for the timber frame I'll be using 100x47 mm C24 timber.

So based on the above my 3 questions are:

1. What size timber should I use for the ridge board and do the lengths go up to 8m?
2. Will 150 x 47mm C24 timber be fine for the rafters?
3. Will using 100 x 47mm C24 timber for the building frame be structurally acceptable?

I'm hoping once I have designed it all to start building next year and would do another build thread.

Many thanks in advance.

 

[ssdave]

....

 

[azmontana]

Its in the UK, minimal snow and wind load.

 

[GMCGarage]

Hi All,

Been a while since I was on here. Last garage I built was a 3 car garage in the UK. It was made from brick. Build thread is on here

I'm looking to build a new garage but to keep costs down want to this out of timber. Size will be 8m x 4m x 2.4 eaves and then a pitched roof with a height of 1.5m.

As I want to fit a lift in the garage I'm wanting an open span roof. I wanted to know what size timber should the ridge board be. I'll definitely be using C24 but unsure on size or whether I can get something which will span 8m?

For the rafters I believe 150x47 mm C24 should be fine as the lengths will be 2.5m.

Also for the timber frame I'll be using 100x47 mm C24 timber.

So based on the above my 3 questions are:

1. What size timber should I use for the ridge board and do the lengths go up to 8m?
2. Will 150 x 47mm C24 timber be fine for the rafters?
3. Will using 100 x 47mm C24 timber for the building frame be structurally acceptable?

I'm hoping once I have designed it all to start building next year and would do another build thread.

Many thanks in advance.

I would suggest hiring an engineer, not trying to get a freebie from here.

 

[azmontana]

I would suggest hiring an engineer, not trying to get a freebie from here.

Didn't realise we can't ask questions to those who know more? I'm pretty competent myself and as you can tell I've done my own research but would like some validation as to whether I'm on the right lines.

 

[GMCGarage]

Didn't realise we can't ask questions to those who know more? I'm pretty competent myself and as you can tell I've done my own research but would like some validation as to whether I'm on the right lines.

Then here are some answers

1. You will need a laminated timber to span the 8m.
2. Depending on the load, the rafters will be fine. What is the required loads per the code?
3. The building frame will be a factor of the loads, again what loads are required by code?

 

[firebirdparts]

I agree totally with the above GMC garage. You need an engineered item of some sort to span 8 meters with that sort of weight. The rafters will be fine. About your third question, this is a very modest building, and so in the USA nominal 2 x 4 lumber, which is more exactly 38 mm by 89 mm, would be graciously adequate strength-wise. Your "100 by 47" is obviously going to be similar.

When you ask about framing on here, about 80% of replies are just telling to you go to hell. My suggestion is that you ignore those. It's always the same deal. If you defend yourself, you just make it appear that you're actually reading them.

 

[ssdave]

.......

 

[azmontana]

So after some more research I was learning about Ride boards instead of ridge beams. Not much information on the internet about this. But with a ridge beam design the roof strength comes from the rafters creating an opposing force and hence the ridge beam can technically be as long as needed?

Can someone with more knowledge advise whether a roof design with a ridge board is possible to span 8m?

 

[oldcarpenter]

completely doable with ridge board provided that you also install collar ties on the rafters


Sent from my iPad using Tapatalk

 

[My Old Tools]

If you want to timber frame it, get a copy of Steve Chappel's book, 'A Timber Framer's Workshop'. It has all the structural formulas as well as the joinery you can use.
https://www.amazon.com/dp/188926900X/?tag=atomicindus08-20

 

[Samh]

Traditional timber frame doesn't use a ridge board, it uses bents with girts and purlins.

 

[ssdave]

Semantics problem between countries. Where we are hearing "timber frame", he's really talking about light frame construction. Look at the lumber he proposed using.