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So our crappy conservatory is basically falling apart. Its a sauna at the moment and a freezer in the winter so we want to replace it with an oak framed (yes yes, middle class STW FS riding Audi driving cliche..(I don't have an Audi)) thing as above.
Chap 1: "So I use air dried oak for the frames. It's the only way to do the job properly"
Chap 2: "I use green oak for the frames. It's the only way to do the job properly"
..
.
Me "Arrrrghhh"
Internets seems divided on the issue.
Now I am sure there are people on here who have experience as an end user and as a subject matter expert. I would really appreciate some advice please. I can do medical stuff but this is causing me a headache!
Thanks......
In my experience it depends on the construction. My rafters are air dried and the purlins and ridge are green oak from a reputable source
It will possibly boil down to cost for you. Green oak is cheaper to buy then air dried/seasoned oak, it also easier to cut, bore and chisel and less demanding on tools.
It will move and shrink more than the stable air dried, so the joints will look more gappy as the green oak dries out. This doesn't unduly weaken the joints, as the strength is in the draw-bored pegged mortise and tenon. Green timber will also have a far higher tendency to move and twist, especially as people seem so keen to wrap and seal up an oak frame building so soon after it has been raised. Therefore, you need to consider very carefully what method of glazing you decide upon. Personally I'd recommend the over glaze method, whereby the glass panels 'float' on the outside face of the frame and held in place by air dried oak capping rails, headers and cills.
If you go for air dried oak, you could get away with casements fitted within the oak frames as the likelihood of any major glass shattering movement is very much reduced, just make sure the templates for the casements allow at least 15mm clearance all round and use compriband tape to seal them in.
Provenance: I used to do a lot of oak framing, including final fitting out and especially the glazing.
Why oak?
What's a 'sustainable source' for oak?
Oak framing won't make a difference to the overheating or over cold. Proper roof and insulation will.
Oak because other bits of the house are already oak. And we want it to tie in.
Current conservatory has a glass roof and we were thinking a solid roof or maybe an orangery style one to mitigate heat loss, that plus better glazing. Its not going to be big though . 3.8 x 3.4 meters and I wonder if an orangery style mansard roof with lantern may look silly with such a small footprint too.
slackalice - does the small footprint change your view at all on green v. Air dried?
thanks all - grateful for this!
Footprint size won't matter, wood is wood, green or dry. A smaller well proportioned frame will cost less overall than a bigger one.
Mansard roof, quality double glazed panels and good insulation would be my choice.
Mansard roof, quality double glazed panels and good insulation would be my choice.
+1 - plus I would price up triple glazing, because of the reduction in light/heat admittance in summer.
Thanks team. The mansard design is the green oak team. The air dried guys proposed a traditional pitch roof with a shallow pitch and fully glazed end wall. Costs are not dissimilar, I think because the mansard roof with lantern is more expensive and offsets the green oak v. Air dried cost.
Why oak?
What’s a ‘sustainable source’ for oak?
A sustainable source is oak forest specifically grown for the purpose, much like other plantations. Elm would be a good alternative, except all our mature trees died out years ago, and new elm doesn’t grow much bigger than a few inches in diameter, sadly.
I make a lot of oak buildings, roughly 2 a week. I agree totally with the comments above from slackalice.
We use air dried oak in the superstructure and laminated oak in the opening doors and windows to cut down on the possibility of warping.
There is a chance that one of the people above is one of my sales team so I won’t go further than to say we use air dried as we believe it’s the best for water tight glazed buildings. It costs more than double green oak prices so if we could ‘get away’ with green and increase our profit margins like our competitors, we would of course. But we can’t, so we don’t.
suggest you ask to see a site that whichever company has done and talk to the owner. Some complained look after thief client far better than others and of course, quality standards are different even if design looks the same.
id much rather give any further advice off line, or even face to face if you wanted to see my factory, please pm me as I’ll now back away from the thread.
Hmm, predictive text has battered me there. was supposed to read
‘some companies look after their clients better than others’
What a spoon.
Thanks tinybits - I have sent you a pm..