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WA_decker
24th August 2007, 02:54 PM
Hi there,

If you are interested in trying to work out all your bearers and joists for both decking and combined roofing, look no further than this great little gem of software I found on the timber.org.au website called Timber Solutions V2.02....great help!

you can put in the lengths, spans, even select the type of wood you want to use, the joists specings, even the wind and floor loads. I found this very helpful. Hope you do to:2tsup:

http://www.timber.org.au/menu.asp?section=Design&sub=Timber%20Solutions%20V2.02%20Software

WA_Decker

bpj1968
29th August 2007, 10:30 PM
I've tried that program, but can't seem to get it to work. Haven't had time to sot down and play with it properly. does it work with windows vista?

WA_decker
31st August 2007, 01:02 AM
I've tried that program, but can't seem to get it to work. Haven't had time to sot down and play with it properly. does it work with windows vista?

Still on XP. Not going to upgrade till I buy a new PC - Vista's too hungry and no fundamental differencesto XP...but I digress..

Not sure about Vista but it looks like a very basic program. I would not think it would matter.

S

Bleedin Thumb
1st September 2007, 02:54 PM
Deckie can you explain how you can get this program to calculate joists and bearers.
I can't get it to do that.
Cheers.

bpj1968
7th September 2007, 10:42 AM
Finally got it to work. Bit hard without the HELP files.

Bleeding thumb, when I got to the timber charts, I had to "refresh index file" for it to work

then with the buttons, select member. eg bearer. and type deck etc.
then geometry. Span - There are 3 figures, the 1st is eth min span to calculate, the next is the max span and the 3rd? (I think this is the increments of span)
Floor load width is how much joist span it carries. i.e 1/2 the distance either side of the bearer to the next bearer. can be any figure, or multiple figures.
Loads - just use teh default
select timber then calculate.

THere is also a part that allows you to calculate cost and compare differnest timbers.

bpj1968
10th September 2007, 10:25 AM
I got tis PM from Scott and thought I would post the reply which might help others.


Hi

I am trying to use timber solutions but i am a little confused, i was wondering if you could please help me. I am currently building a deck and want to put in the following info. My support piers are going to be at either 900mm or 1500mm apart and bearers 1500mm apart. I dont know what to put for Bearer span and floor load width. if you could please help me that would be great.

Regards
Scott

Bearer span has 3 figures. the first is the minimum span and the second is the maximum span. the thrid is the increments (eg 100). This will give results of bearers and the maximum span they can handle, to the nearest 100 mm, or whatever figure you use as the third.

For you

Bearer span enter 900 1500 100. This will give you results for various bearers from between 900 and 1500, at intervals of 100. i.e. 900, 1000, 1100, 1200, 1300, 1400 + 1500. It might pay to put in 900 1800 100 that way the spans will go up to 1800, which will give you an idea of eth load they can handle. as a bearer that is only just suitable for the span may be a little springy.


FLOOR LOAD WIDTH

each bearer shares the load of the floor between itslef and the next bearer. Floor load width is half the distnace between bearers, on each side. In you case it supports 750mm of the floor each side, FLW = 750+750 = 1500. (It is usually the same as the bearer spacing, unless bearers are spaced differently) The bearer at the outside will only have a FLW of 750, as it only supports one side, and only has a lesser load, however most people use the same size for appearance.

When you work out the floor joists, you could use 1500 1500 100. But that will only give you span results of 1500. Instead use 1200 1800 100 This will give you span results between 1200 and 1800, which will be a better idea of the span each can handle.

Once you have used the span tables to calculate the spans of the bearers and joists go to the "specific design" and enter the exact values for the spans, then select timber etc. You then generate the possible choices, with percentage load. 100% is at maximum load, which is probably not the best choice and may be better to select teh next size up.


You can even enter prices for the various timbers, using the tabs at the top, which will give you a price.

Bleedin Thumb
10th September 2007, 11:10 AM
Good stuff BPJ. I will have a go when I get a spare moment. Thanks.

bpj1968
11th September 2007, 11:02 AM
I have put a few screen dumps on.

1. simple how to select bearers.

2. values for geometry

850 2648 25
1200 1666 2400

850 = smallest span
2648 = largest span.
25 = max span for each size bearer to nearest 25mm

1200 1666 2400 are the floor load widths (FLW). (Can have between 1 and 3)


3. You can change the load values. Balcony load pressure has a default of 3, but it looks like it should be 4 for above 1 metre, and 2, for less than.

4. The resulting span table. As can be seen the results are to the nearest 25 mm. The larger size bearers only show up to 2648 mm, which is the max value I entered at 2. The can no doubt span greater distances.

WA_decker
11th September 2007, 06:04 PM
Hi there,

I used it pretty much well like Bryan said. I also got a PM from srohara (Scott) requesting what I did and I will share my response to what I did in the end...

Hi there,

I have been going through a whole range of decisions like the ones you have been I am sure. I am fairly new to this as well. Not sure where you live, but I live in Perth. I have found that you can pretty much well have a whole range of bearer spans and joist spans depending on what wood you use, etc.

What I found to be the most cost effective wood here is MGP10 H3 Treated pine. I think its cos its used a lot here in the roof building industry. So then I went to Bunnings and two other timber yards to see what was the most common sizes out there and relative prices. What I found is that if you have your bearers supported by posts or stirrups about 1500 apart that is fine. Coming away from the wall (I am bolting my deck to a wall ledger (fancy name for the bearer attached to the wall) It is recommended that you have the distance between the wall and the posts between 1500-1800.

In terms of wood, I have found that H3 Treated Pine 190 x45 is perfect for the bearer spans I have listed above and 90x45 for the joists. If you have a big table with heaps of chairs (like I do in one section) then I would make the gap between the posts/stirrups/footings 1000 instead of 1500.

And after heaps of reading and looking at this site that is what I gathered - that for the cost, its always a weigh up between the amount of posts you are willing to put in compared to the thickness of the wood to span - in the end although I didn't want to dig too many footings cos its a pain in the ?????, I am putting in around 40 concrete footings and stirrups, but it is a 72sq metre deck.

My deck will extend 3500-4000 from the house wall and about 10 mtrs long on one side and 7mtrs on another (its an L shape). I didn't want to put a bearer between the 3500 span running paralell with the house at 1650. So I used this program to calculate the wood span I would need to do such a thing. In the end it was going to cost too much so I went back to the 1500 footing span recommended by two of the three timber places I went to.

Hope this helps. Let me know if it doesn't. I did use the application and got it to work OK. the only thing was that to put the least amount of posts in (didn't want to work too hard with the footings, etc) I had to buy thicker timber that would have costed an extra $700. So in the end I decided that more footings (more work) and less costly wood was the way to go - its a home job, so I have the time...money...well that's another thing. If this was a job for a client, I am thinking to save myself work I may have just priced thicker wood (greater spans) with less footings (work for me)...but its for home so the choice was less cost, more work.

Not sure if that answers your question in terms of the software, but simple is best and 1500 spacings on footings with the wood recommended above is waht I found to be the easiest and I am confident it will hold and not bounce. (its almost overkill, but not enough for you to think 'too hard' I prefer to spend the extra.)

I dug 15 footings (300x300x300) on the weekend and it was fine. I think I may well have spent too long planning and not enough doing. When I got into it, the extra footings aren't really a massive issue. I have estimated about $20 per footing.

Not sure if my answer is a little off track but thought I would comment on where I have gone from finding this app. Its great if you need to work out spans, I found that supply of common wood sizes and its price ultimately was a major factor in my selection.