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Our designer has spec'd HySpan and HyBeam members for our floor. I haven't had any experience with these and just wanted to know what people think. I know they are a laminated product and so they should be pretty strong. Some of the sizes look a bit small to me though: eg. bearers are 140mm by 65mm, joists 100m x 45mm. In hardwood, that would be like a trampoline.
The sizes are punched out by their design software so I guess they are right. I don't want a bouncy floor, so what do you reckon?
If you do a search there are heaps of threads on this subject, Ive got them in my house 200's spanning 3m and they are fine. The bearers will be no problem, if you are really concerned just go up one size and you will have no problems at all.
OK, I did a search but only found 4 threads with Hyspan mentioned. I guess what I want to know is whether or not these small sections have any bounce in them. I know it depends on pier spacing but 140mm for a bearer just sounds a little on the small side to me. 200mm is a different story.
They sound a bit on the small side unless the FLW's are closed right up - have a look at their tables (over 1 meg): http://www.chhfuturebuild.com/upload...bles_Mar05.pdf.
Are you sure they're quoting Hybeam and Hyspan (CCH Futurebuild products)?
If concerned you could ask CCH for a bit of technical info - 1800 808 131
Thanks Eastie. Yes, it's LVL Hyspan and Hybeam. Looking at those tables, there's no such thing as a 140 x 65, so I'll have to look at his spec again.
Anyway, for continuous runs, they say a 150 x 63 (let's give him the benefit of the doubt) will span up to 3.3 with a FLW of 1.8, so if the piers are 1.8 apart, that should be plenty.
Hyspan's a good product with a good reputaion.
Check out the span tables, but you should have no reason for concern if they have been calculated in accordance with the Hyspan software.
You haven't mentioned the spacing of the posts supporting them, so it's impossible to make an intelligent guess or even comment as to the adequacy just on the information supplied in your post!
The load carried is a function of the area of floor supported by the span.
More posts, smaller spans, smaller timbers = less cost. If it's marginal, up the size to the next increment, and wait for the estimate of cost!!
Cheers,
P :cool:
Yes I realise that. I haven't got it in front of me though. It's just a general question as to how good the stuff is you see. I've paid a designer to spec it and he has used the LVL software to do it. I just don't know anything about it.Quote:
You haven't mentioned the spacing of the posts supporting them, so it's impossible to make an intelligent guess or even comment as to the adequacy just on the information supplied in your post!
It's about as good as it gets IMHO. Not as cheap as it gets but usually worth the extra for the stability alone, the termite resistance is a bonus.Quote:
Originally Posted by silentC
The vertical laminates mean NO movement from shrinkage whatsoever, so provided it's sized correctly and your footings are right, you should have no settlement issues.
Cheers,
P
A builder I know loves the stuff because he can pick up a 6 metre joist and walk along a bearer by himself like a tightrope walker. Sometimes what's best for the tradie is not necessarily the best for the householder though if you know what I mean.
I also wondered if going up in size and having fewer piers would be cheaper because there's less bricks to lay. I suppose you lot up there use steel posts or concrete stumps like those mad Victorians do? Maybe I should look at that instead of brick piers.
Yep. Why would you pay a bricky to stooge around and not get things quite right, when you can just drop gal steel in, perfectly plumb and level, and simply bolt it to the bearer?
More posts = smaller spans and less deflection. From memory, allowable deflection under the code is a percentage of the span, so upsize the joists/bearers by all means but keep the spans as small as economically possible.
If the allowable deflection is l/300 (I'm guessing now!), a three metre span is designed to deflect 10mm, a 1500 5mm : which do you think you'd notice less?
That's just one reason why a small increase in span can often result in a large increase in timber size.
Back to builders liking them: I like them because they are STABLE.
Cheers,
P
You know, I'm glad to have such a wealth of knowledge on tap! So, steel piers for me and plenty of 'em :D
SilentC
Hyspan is a registered tradename. Check the following link; they have all the span tables and other tech data:
http://www.dindaslew.com.au/hyspan.htm
If you know the loading & spacing, then you can check the suitability of sections yourself.
If in doubt, you can fax your drawing / details and they will tell you.
I used some of their products as internal beams (240x673 and 300x63). Easy to work with. Seen a bit used as upper floor bearers & joists.
Cheers,
Theva
OK, so what do you know about Lysaght Uni-piers?
Maybe some of the humpy-builders in our midst can enlighten us! I've never seen the point in having an adjustable steel column!
Just go to your local steel fabricator, if they don't already stock standard lengths of column, get them to weld a flange on the top, and bottom, and stick it in the appropriate sized hole full of concrete, prop it to level and go and have a nice cup of tea with Uncle Bob.
I used to bolt them to the bearers, then prop the bearers with Acros till they were dead level, suspending the columns in the footing holes before concreting.... but that was too hard for no difference in end result!
The unipier type things seem to me to be a way of turning something simple into something that's not. Now tell me they are REALLY cheap!!
cheers,
P
No, I don't reckon they'd be cheap. Probably cheaper than brick piers. Maybe.... But then my Uncle Charlie is doing my bricklaying, so maybe not.
The main advantage of the Uni-pier, apart from the adjustable bit, is that they have an integral pier cap as well. But then I'm buggered if I can see how a termite can get into the bearer from the outside of a 90x90 steel post embedded in concrete, unless it's through the concrete pad and up the middle of the post. Anyway, I can make my own. Used to make pier caps for 10 cents each in my old man's sheetmetal works when I was a kid.
I reckon there's something to be said for bolting them to the bearers first. If the bearer is in position, then you don't have to check each pier and you don't have to worry about the strange habit posts have of moving as the concrete cures. I'm sure that bloody thing was plumb yesterday - yes there is a carport somewhere in Sydney that has one post with a slight lean on it.
Why did you find it too much trouble?