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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?
Cos as you say piers have this strange habit of moving! If the plate at the top wasn't exactly square to the post, you're building in an instant angle! To fix they need to be clamped and wedged plumb, while dangling in wet concrete.Quote:
Originally Posted by silentC
By the time you've done that, you can stick two stakes in the ground, clamp two braces on the post and walk away! Then you only have to lift the bearer onto it and bolt it on the next morning, no props no mucking round no nuffink.
Cheers,
P
... and hope that you didn't put one in a tad too high ;)
I was just talking to my mate Muzza and he reckons that even with 90x90 post with a flange on the bottom, council still might insist on a pier cap. Dunno how we put a pier cap on top of a post that has a tie down plate welded to it. I'm going to suggest that we weld an L shaped plate on the top of the post. No termite is going to chew through that.
Another suggestion was a seperate tie down rod next to the pier. That might be even better. Dead simple, just a rod with a cross piece on one end bedded in the footing and wrapped around the bearer. I think I like that idea too....
I think Ive posted this before but here goes, I have 16 posts like the 2 in the photos. I had to get the pad for the house cut then dig down 1m from the level ground where I had 750x750x300 concrete pads with 2 layers of 100mm reo top and bottom. I got them level and poured them first. I then bought 9m lengths of 90x90x2.5 RHS, I also bought 200x200x8 plates with 4 holes already cut. I made up a jig to keep the plates square to the posts and welded them on. I didnt worry about getting the concrete pads all the same height, my old man and i used a dumpy to get a measurment for each pad and cut the posts to match. Used a $99 hammer drill from bunnings and drilled 64 16mm holes 150mm deep and used threaded rod with ramset chemset(great stuff and the drills still going strong). Bolted the posts to the concrete and squared up the posts(lots of cheap clamps, I think I bought about 50 from the warehouse). I then placed the UB on top of the posts and bolted 90x45 to the UB then the joists on top. I boxed up around the post and poured more concrete around it back up the 700mm or so to where the ground level is then back filled with dirt. Easy as that(yeah right)
Dumb question Silent - can you do a concrete floor (after a bit of earthwork of course)?
Nah, sloping block. Falls about 3 metres from the top corner to the bottom. We're having a storage area in underneath at the lowest point as well. The top half of the house and the garage are on a slab but the bottom half is not.
No problems... that's what stringlines are for! In anycase, a tad is an acceptable tolerance in a timber floor!Quote:
Originally Posted by silentC
Council's aren't clever are they? The ant cap DOES NOT, nor has it ever been intended to prevent termite attack.
Originally it prevented termites boring up the insided of timber stumps and straight into the floor framing, then with the advent of brick and concrete piers, it provided a visual indication of where the little suckers were.
Remember, termites don't like light, so build tunnels over masonry to get to timber. All an ant cap does is gives them something to go round, and you the opportunity of seeing them do that.
If you use a horizontal flange on the stumps, and bolt vertically through the bearer, you have a barrier already. (You can also put a tin cap over the flange if push comes to shove, and bolt through the lot.)
There's no shortage of strangely erogenous cranial deformity in local government is there?
Cheers,
P
It's surprising how many people don't understand that. One guy said to me that, even if the termites can't get up the middle of the post, and assuming you can see the mud trails up the outside, you still need to do something to prevent them entering the building - hence the ant cap. I explained it to him but I don't think he believed me.Quote:
The ant cap DOES NOT, nor has it ever been intended to prevent termite attack
I think I might make one of those piers, take it and a short section of bearer, and maybe a bucket of concrete, to the inspectors office. Then I'll challenge him to show me how a termite can get in, short of levitation, without me knowing about it.
Unfortunately logic, or even proof, does not often work with these blokes.
Our designer put our DA in with a low fire danger rating. The nearest continuous dry bushland is more than 100 metres away. There is a gully running through the block but it is wet - we cannot clear it or build within 40 metres of it without approval as it is a natural water course. The shire fire officer comes out and says "nope, level 2 construction required". He says the strip of bush in the gully is dry forest. OK, we say, let us clear it and thus remove the fire danger. No, you cannot because it is a natural water course and therefore protected. Doesn't that make it wet forest then? Blank look. HELLO!!!! Is there anybody in there? Termites, water, or both on the brain I think.
The real reason is that the bloke three doors up was given a level 2, so they would look like right plonkers if they gave us low and he found out about it.
Fire design is a bit of an interesting one.
Vegetation to be cleared for 100m, so that's 3.2 Ha surrounding your house.
As far as I can tell from the regulations, this is only at the time of approval/construction. Once you have your final certificate, you can plant trees to your heart's content.
Figure that out!
cheers,
P
In NSW you are supposed to implement a 'site management plan' which basically means you agree to keep your asset protection zone (APZ we love our TLAs) clear of undergrowth. The size of the zone depends on the site analysis and blah blah blah.
Now, my block is 60 metres wide. My house is 40 metres wide, so that gives me 10 metres either side. The blocks on either side are both vacant so no 'site management plan' has been implemented there. Am I meant to keep the vacant blocks clear too? What am I going to do in 5 years when they are still vacant (which they probably will be) and covered in regrowth? Because the land owner has not lodged a DA, as far as I know he is not under any obligation to keep them cleared.
Idiots...
...that's a big house. Are you sure you haven't sneaked a big shed into the middle of it?
It's a 3 bed/4 bed dual occupancy with a 2 car garage in the middle. ;)
There's is a nice big shed going in down the back though. Pegged it out on the weekend - 16m x 6.1m. Still doesn't look big enough. :(
I've just used Hybeam on top of 'c-section' steel piers and bearers (100x50mmx3mm) - can't be happier.
I went down the path of uni-pier and another similar 'system' but you can only purchase them in the 'system' designed by their engineers - was going to cost around $3K for a 16m2 room.
I've just posted the progress photos of the job in a separate thread.