Thread: Roof truss repair

We have recently done an building inspection report on a townhouse that we are interested in buying.

The inspection report states that there is a "structural defect" related to the timber truss construction in the roof cavity. There are pictures on the report showing two roof trusses were cut to make room for the ducted air conditioning unit. It is recommended a roof carpenter is engaged to assess and provide repair advice.

I called a truss supplier company and was advised to find out the name of the developer, ask the developer for the name of the truss manufacturer, go to the truss manufactuer for advice in finding someone to do the repair work.

The problem is that the townhouse was built 10 years ago. The council does not have information on the builder.

We requested the seller to do 3 things:
- repair the truss
- have the air conditioning unit relocated and properly installed and
- provide an engineering report confirming that the roof, after repair, is structural sound

The seller arranged a builder (not the original builder of the townhouse) to inspect the roof. We were told that the builder has advised that 3 "support beams" (not 2 as mentioned in our building and inspection report) will need to be replaced. The cost is around $1000. The seller agrees to fix the roof at her own expense but does not agree to relocating the airconditioning unit and providing an engineering report confirming the structure is sound.

Some questions:
- is roof "support beams" the same as roof "truss"?
In the building inspection report, the term "roof truss" is used. I've actually called a number of roof carpenters. Whilst the roof carpenters can handle a traditonal roof repair, they don't do roof truss repair. I was told that roof truss is usually manufactured in the factory and the weight load needs to be carefully calculated with computer programming.

The seller is getting a builder to replace the "support beams".

- Does $1000 for this kind of job sound reasonable?
I was told that they will be putting in the wood with bolts and there is no need to move the air conditioning unit. The wood put in could be removed when needed.

I have no clue whether this is the proper way to do the repair. We have very bad experience with repair contractors where the repair work is more cosmetic than functional. In fact a bad repair job can do more harm than good to the house.


- Is an engineering report confirming the roof is structural sound, in this circumstance necessary?

The real estate agent keep telling us that nothing went wrong in the last 10 years. For a roof of this size, most builders will not even put in truss to support the roof. It is not a structural issue as the truss is something extra. The seller is getting someone to fix it to make it 100%.

No clue whether the truss is necessary to support the roof or it is something extra. I would imagine no builder would spend extra money to put in something extra if it is not necessary. As it's all about making a return on the project.

I am skeptical that it is not a structural issue and the fact that nothing happened in the last 10 years does not mean that the existing structure is sound. It could be hard to detect with our eyes but it could deteriorate over time. What we worry as new owner of the property is that we may have to fork out money in the future to fix any pre-existing problem. Besides we are not sure if the building insurance will cover damaged caused by the previous owner.


Given the seller is not willing to provide an engineering report, we are thinking of getting it done ourselves just to make sure the repair is properly done and we don't have any issue with the strata corporation or the building insurance after we took over the house.

Any idea who can do this engineering report ?


I've attached the pictures of the roof truss per the building inspection report in this posting.

Thanks in advance
Any idea and suggestions would be welcome and appreciated.

The real estate agent keep telling us that nothing went wrong in the last 10 years. For a roof of this size, most builders will not even put in truss to support the roof. It is not a structural issue as the truss is something extra. The seller is getting someone to fix it to make it 100%.

Ignore what the real estate agent is saying, they are being paid by the vendor, and of course the vendor doesnt want repair costs eating into any margin they may have.

The trusses are what hold your roof up. This IS a structural issue. If the trusses have had sections removed the strength of them will most likely have been compromised, the level of compromise is something best left to an engineer to establish. From the description you provide it sounds as though the builder is going to bolt timbers back onto the trusses in an attempt to re-instate them. This type of repair was common when gravity feed hot water units were installed/maintained in the roof space. The strength of the repair will largely be dictated where the builder re-installs the timbers (I would venture to suggest that this wont be in the same place as the originals that were cut because the ducting is in the way). If this is the case logic dictates that the characteristics of the truss will have changed and should be re-assesed to ensure that they are fit for purpose. Its entirely possible that the repair will be quite suitable and everything thing will be ok, also entirely possible that it may not and you may end up having to make repairs in the future.

If I were in your position I would be sticking to the line, "Repaired AND Certified" (the aircon doesnt necessarily need to be moved to effect an adequate repair of the trusses). You are totally justified in your concerns.

A structural engineer would be able to asses the proposed repair on paper before it is carried out (they will possibly need to visit site to obtain truss construction detail) and then again by inspection afterward. This, however wont be cheap (anywhere upto a couple of grand at a rough guess), which is why the real estate agent is pushing you to sign without the certification.

As for cost of repairs, a thousand dollars is probably around the mark, I had a strutting beam replaced a couple of years ago (2008) and it cost between $500 and $600 from memory (I provide this as a guide only because my house is of entirely different construction to your intended purchase comparison should be drawn on the basis of labour and not construction techniques). I personally wouldnt be concerned about the cost, you will be better served having the vendor effect the repairs and having them certified as opposed to them offering you a thousand dollars or so off the price (which is where it looks like they may be heading).

I hope that helps a bit. Best of luck with it.

sounds interesting, I'd be getting quotes for all you want then subtract that from what you were going to pay them, that way the tradesmen work for you at their cost, perfect

cheers
Pulse

Pics would be good, here's a link to help.

http://www.renovateforum.com/f36/add...ur-post-91653/

Here are the pictures.

Thanks racingtadpole for your comments.

The seller agreed to pay for the costs of the repair and have it done before the settlement, but not the engineering report to confirm that the repair work is proper and the roof structure, after the repair, is ok

Can someone please provide a lead/contact for the structural engineer that can do this job?

Whoever did that needs taking out the back never to be seen or heard from again! As it happens there is safety factor built into designs, but it isn't supposed to be taken up by idiots simply cutting into trusses!

But strengthening and re-strutting (from what I can see in the pics) should be very straight forward and any qualified carpenter should be able to do the job (as indicated by your building inspection report). Unless you really really want an engineer I would just make sure you see what the chippy does and take some more pics. Also insist that the person really is qualified (get the estate agent to show you their licence photocopy - or a web link to prove it!) not simply the real estate agent's handy person. If it's been like that since the A/C went in and there are no obvious problems then they are highly unlikely to appear after strengthening is done. Your call of course.

Thanks everyone

The seller revised the special condition in the sales and purchase contract. All they agree now is that before they hand over the house to us,

"the vendor shall at her own cost and expense and in a proper and workman like manner using a qualified tradesmen, arrange for three support beams in the roof to be replaced".

So the second and third condition ( relocation of the aircon and engineering report to confirm that the roof structure is sound) were not accepted.

We are first home buyer and have no experience with fixing the roof or any renovation work. This is the second house we entered into a contract. The very first house we were interested in buying costed us a couple of thousands (deposit, lawyer fees, inspection reports). We pulled out the deal at the last minute because the building inspection report shows all the renovation work done by the owner were just cosmetic. We were in a way lucky as on the day of the inspection, it was raining heavily. The subfloor was full of pools of water. The downpipes were not properly connected to the storm water drainage and were blocked. Everything was just not right...... We have heard a lot of stories where the seller spent a few grands to renovate and cover defects before selling it at a much higher price than it is worth.

We learnt our lesson and it may sound pathetic, we are trying to be really carefull this time and not waste another few thousands hard earned money.

We was worried that the truss repair job for this house that we are going to buy would not be done properly. Firstly because the licensed builder is the agent's contact. Secondly I have no idea whether replacing the "beams" is the proper way to repair the truss". Thirdly the job only costs 1K and the seller does not agree to providing an engineering report. It would just be a quick and dirty job to get the deal through.

Thanks everyone for your time in replying. I've requested the real estate agent to provide the report they received from the licensed builder who will be doing the repair work and I will request the builder to provide pictures as evidence of work done.

I can understand with that experience you are a bit nervous about the whole deal. The reality is that no house is perfect and interpreting the builders report is as important as getting one in the first place.

The best way to be sure it is done to your satisfaction is to organise the chippy yourself or go there after their chippy and take some pictures yourself to show us prior to settlement. Don't ask them to take photos as proof that it was done, that shows shows you don't trust them, remember some stupid AC installer did this without their knowledge! Relax and the deal will get across the line.

Cheers
Pulse

The first picture shows a saddle truss that has had its bottom chord cut. No big dilemma there. A saddle simply acts as a wall frame and transfers the load directly down to the jack truss (assuming from the top pic) it is sitting on. Amke sure there is a multi grip fixing it to each truss underneath it, then run a batten on the top chord of the trusses supporting the saddle, either side of the saddle as close to the saddle as you can with just a nominal fixing. Saddles act like the roof battens for the truss below and stop them wanting to buckle.


The pic that concerns me is the lower one. It is a what is referred to as a truncated truss. I want to know if there is a truncated truss in front of it taking the jack loads or the jacks are fixing to the truss in question top and bottom. I'm assuming not, though are we would see the result of that.

The saving grace is the webbing was removed from close to the centre of the truss where loads are less, generally speaking. I can see no deflection or bending in the horizontal top chord in the second picture, not to say there isn't any. As Bloss mentioned, trusses can be, but not always, forgiving.

What you want to do is this.

Climb up in the roof again (a pain I know), and get the brand and model number of any air con plant sitting on the trusses. We need to know its mass. You can call the manufacturer and get that easily.

Then look on the metal nail plates. Get a close up picture of them or look very closely and they will be stamped with either Pryda, Multinail or Gang-Nail (Mitek).

Call the Sydney office of the nailplate supplier and request a site inspection informing them that you are unaware of the original truss plant that supplied the trusses, but let them know the name on the nail plates.

The going rate is about $180 per hour including travel time. Allow an hour on site, and up to 2 hours for analysis (as they don't have the orginal plans and reverse engineering is a pain in the @@@@.

You will be offered a detail for rectification signed off by a cert.Engineer. Take this to a carpenter and have them carry out the rectifications as per the detail.

Everyone is happy. These things do happen - alot. Dopey carpenters who do just this sort of thing kept me in a good lifestyle for 20 years.


The thing that strikes me more than the cut webs of the trusses is that the jack top chord to the horizontal top chord of the truss seems to have no connection of note. Neither does the the saddle bottom chord to the jack / truss top chord in the top picture. The picture isn't clear when blown up but there might be a ledger behind the saddle.

Either way, if you find the nail plate supplier and have no luck, post back here and we'll see what we can do.

You know the thing is, that if the original builder had let the truss company know there would be an AC unit in the building, the trusses could have been designed with spaces to accomodate this. But it is also possible the truss company were informed and forgot. Either way, the builder should have rectified correctly in the first place.


Edit: I just realised what you said. The seller is to do the rectifications. Demand you use the services of Paul Davis from Project X Solutions. What he doesn't know about trusses ain't worth knowing and has access to all software for nail plate suppliers. I have no affiliation with him, he's just a damn good engineer.



Cheers,

I think Stan101's post has been overtaken by events. The new contract conditions should be sufficient - strengthening should happen, the A/C has been working in that position for ten years or so, and the obligation is now on the vendor to ensure that it is done properly. All should be good - at least the inspection found it! I had a quick look at a house for the children of a friend after contracts had been exchanged and a building inspection report done and discovered some significant problems, none that would be dangerous, but costly even so and very obvious - they negotiated a discount off the price and we fixed later, but not good.

What amazes me is that even in the ACT where building inspection reports are compulsory and at the sellers expense (not really of course it is in the price), they are simply boilerplate text and checklists and can be provided with qualifications like: "underfloor unable to be inspected due to poor access". What is worse is that lawyers (and the lenders!) still allow clients to continue with the purchase. Fact is most of the time there will be no problems, but the system is supposed out find the exceptions to that rule - how can it if no actual visual 'inspection' has taken place of critical parts of the building?

Of course the building inspectors are licensed and carry insurance, but this is about prevention not a lawyers breakfast after the sale. Ah well - ranting again.

Bloody A/C installers. Believe it or not this is very common, more so in a retrofit of ducted A/C. You have to watch them every second in a new house install as even standing below them instructing them what they can and cant touch, they will try and cut anything that is in the way. A A/C installer with a recipro saw is as dangerous as a plumber with a paslode gun IMHO - lol

MVA, don't be foolish listen to what guys like Stan 101 are saying. Roof trusses are highly tuned engineered products. "Any" modification including repairs needs to be designed and "certified" by a structural engineer. Council approval for the rectification work is more than likely also required. $1,000 will go no where, make the vendor pay, otherwise you may be held liable for any further damage or repairs if you ever sell the building.

The reason I suggest you go through the nail plate manufacturer is not only to get it right, but to have it right with certification for when you go to sell.

We used to laminate certs and with rectification detail and calcs then nail them to one of the trusses involved.

As I said, my concern is more for the tie down of the jacks to the horizontal top chords.

cheers,

Originally Posted by Hoppy

MVA, don't be foolish listen to what guys like Stan 101 are saying. Roof trusses are highly tuned engineered products. "Any" modification including repairs needs to be designed and "certified" by a structural engineer. Council approval for the rectification work is more than likely also required. $1,000 will go no where, make the vendor pay, otherwise you may be held liable for any further damage or repairs if you ever sell the building.

The personal attack is unnecessary IMO. keep a bit of perspective here: this is two changes to a truss done stupidly, but 10 or more years ago with no apparent negative impact.

The OP says the vendor is now to pay - and seems to have legal advice on the contract terms that ensures that, as well as the work to be done by a qualified person. Depending upon the market would you run the risk of not getting the house you want for a maximum $2K problem? They have the cover they need IMO.

I worked as an engineer for the nail plate supplier, who are the engineers for the frame and truss industry. You can contact one of them and get their opinion, MITEK, PRYDA or MULTINAIL, all of them have engineers. Alteratively, find an engineer with roof truss experience. From the photo it looks fairly straight forward but you need to make sure the load is transferred correctly through the connection of the new stick of timber from the existing truss. Also, it is a good idea to get them to assess the existing level of damage caused by the cutting of the truss because you may be able to claim the cost of fixing that too.

Originally Posted by Hoppy

MVA, don't be foolish listen to what guys like Stan 101 are saying.

Originally Posted by Bloss

The personal attack is unnecessary IMO.

My initial reading of Hoppy's post was as Bloss have interpreted it. However, I think Hoppy actually meant the opposite. After re-reading the whole post (and re-punctuating), I think Hoppy meant to say...

"MVA, don't be foolish! Listen to what guys like Stan 101 are saying."

Bloss I apologise did not mean to tread on your toes. I am also and old chippy with too many years of experience and although a good carpenter can restrutt a conventional pitched roof without the need of an engineer, the same does not always apply to a trussed roof.

Originally Posted by Hoppy

Bloss I apologise did not mean to tread on your toes. I am also and old chippy with too many years of experience and although a good carpenter can restrutt a conventional pitched roof without the need of an engineer, the same does not always apply to a trussed roof.

Nah - Chrisp has set me right too!! I misread what you were saying. Must have been tired (or just another 'old-timer's moment!) And I would be wary if it were multiple trussses of course, but this is a pretty basic reinforcing job. In any case the contract changes seem to be sensible and get the responsibility back on the vendor.

If there's a group hug.......I'm outa here.

The guy that did the Building Inspection picked it up and made some recommendations - he should therefore have a reasonable idea if what is proposed to fix it would address the issues and accord with his recommendations...

Short story, ask the Building inspection mob if what is proposed would fix the problem...

Originally Posted by watson

If there's a group hug.......I'm outa here.

We'll keep hands high and no kissing . . .