Thread: Roof framing standards - new house

madrat, your roof uses a 'truss' type construction.
As such it is not likely that you'll find steel members within the roof space.
With a 'stick' type construction beams, whether steel or timber, are often used to span large distances and in turn support other roof timbers.

These are the issues the building inspector highlighted;

1. To comply with BCA AS1684; Bolt or shot fire at max 750mm C/CS WBN / Structerre Concession (at present Tek Screws used) - this is for timber plates on top of UB's.
2. Raft Ridge collars not in.
3. Hoop iron straps are loosely nailed to rafters. No attempt has been made to tension straps. Not fixed to purlins (battens). Suggestion to disconnect straps and 2 x nail to the top plates plus triple grips to fix rafters to plates.
4. Porch and Garage; Plates are not strapped. No soldiers.
5. Under purlins where overlapping and sharing a prop should be bolted together (2x).
6. Alfresco plates on RSJ's are strapped to RSJ (one elevation only!) but rafters are not triple gripped.
7. Props seated on lower flange of RSJ need lateral support.

The wind rating is N1, interestingly someone a few blocks away is rated N2 though there is a lot of variation in elevation in the area which I guess makes a difference.

PS to Madrat - you might want to consider getting some insulation installed.

And not a mention of the loose brick stack?
Must be ok then...?

Originally Posted by Brickie

And not a mention of the loose brick stack?
Must be ok then...?

This was the primary reason I had the inspector out and I specifically highlighted it to him onsite and discussed it. He told me it was ok and acceptable.

As I said earlier, I don't expect this to be changed in this case (unfortunately) and accept that this is the sort of thing that is being done in WA. However I do not believe this should be acceptable practice or allowed by the building codes, as it appears it is (possibly because it is vague in this area) then those codes need to be changed or clarified.

I did have a flick through both the framing standards (non cyclonic) and the brickwork standards but couldnt find anything, maybe its in the steel standards?

Its still bodgy in my mind though.

To comply with BCA AS1684; Bolt or shot fire at max 750mm C/CS WBN / Structerre Concession (at present Tek Screws used) - this is for timber plates on top of UB's.

You will find 0.1% of houses have triple grips to some areas. You are not close enough to the coast to justify the Triple grips.

Are the triple grips compulsory?

Raft Ridge collars not in.

Are you referring to a lack of collar ties?

Hoop iron straps are loosely nailed to rafters. No attempt has been made to tension straps. Not fixed to purlins (battens). Suggestion to disconnect straps and 2 x nail to the top plates plus triple grips to fix rafters to plates.

Ok, maybe a better job could have been done wrapping them tight but wrapping hoop iron over rafters and battens is not the easiest of tasks. If they are flapping with no attempt at tightening then sure get em to tighten them up.

[quote]Porch and Garage; Plates are not strapped. No soldiers.[quote]

What is a soldier? I assume he means kickers?
Strapping plates? Does he mean the wall plate?

Under purlins where overlapping and sharing a prop should be bolted together(2x). (Alfresco plates on RSJ's are strapped to RSJ (one elevation only!) but rafters are not triple gripped.

Yep overlapping under purlins should have 2 bolts.

Props seated on lower flange of RSJ need lateral support.

No attempt has been made to tension straps. Not fixed to purlins (battens).

Yep straps should be pulled up but hoop iron is not something that is easy to get really good tension. The angle they end up on sometimes its impossible in some cases.

How do you get a hoop iron strap from the cavity up to the under purlin?
They're not even delivered long enough.

Where was the inspector from?

This is a Truss with gang nails. Different

Originally Posted by ausdesign

madrat, your roof uses a 'truss' type construction.
As such it is not likely that you'll find steel members within the roof space.
With a 'stick' type construction beams, whether steel or timber, are often used to span large distances and in turn support other roof timbers.

Thanks Peter,
I guess I was looking for something that didn't exist-typical.
(who's an idiot then? )

[quote=Arc;
PS to Madrat - you might want to consider getting some insulation installed.[/quote]

We were going to get insulation, but we are getting the roof repaired and repainted with insulpaint (apparently this paint will make a massive difference to temperature and air con usage to the point where we may not need it. So we'll see if it is right or whether we have been duped).
Cheers and good luck. I will continue to follow this thread, that's for sure.

If there were more people who wanted to know & learn it would probably make my work easier overall.
the only 'idiots' are those who don't ask.

Originally Posted by ausdesign

If there were more people who wanted to know & learn it would probably make my work easier overall.
the only 'idiots' are those who don't ask.

Thanks Ausdesign.
I tend to feel like I waste people's time who are in the know when I ask, but when I do, it's truly to learn and understand, so I will remember that.

Why dont you email the WA institute of building surveyors [email protected]<SCRIPT language=JavaScript type=text/javascript> <!-- document.write( '<span style=\'display: none;\'>' ); //--> </SCRIPT> with some pics, and mention that you have heard this is common practice. See what there comments are.

Originally Posted by madrat

and repainted with insulpaint (apparently this paint will make a massive difference to temperature and air con usage to the point where we may not need it.

Ive got a big bag of magic beans too if you are interested..?

Originally Posted by Brickie

Ive got a big bag of magic beans too if you are interested..?

hee hee.
That would be nice.. How much?