Q&A with Handy Mac: Fixing a chimney
Q: I am turning to you in desperation. I hope you might be able to recommend someone who can rectify a construction problem at a property I let.
The original builder built the chimney on top of a wall plate, but did not isolate the cavity wall from the chimney. In addition, there is a wooden roof truss built into the same chimney cavity.
This is both illegal and highly dangerous. There is heat damage to the wooden truss, which will have to be reinforced and rehung on the repaired chimney.
Roof battens will also need to be replaced. I contacted A19 inspections to assess the faulty work, and give me a report on what needs to be done to bring it up to the acceptable building regulations. – Mike
A: Mike is in contact with contractors for quotes, but let’s look at the problem. It is becoming more prevalent as building standards drop and anyone can be a contractor as developers want to throw up complexes as cheaply as possibly.
Years ago, I inspected a complex where about 50% of the units had this problem. I also remember a multi-million rand fire caused by a truss built into a braai chimney.
This should never happen if proper procedures are followed. We have building inspectors, architects, engineers and the contractor checking every site so how is this missed?
Easy – someone is not doing their job and the contractor goes ahead without concern about what the negligence might cause.
I imagine the thinking is that the truss is so far from the fire in the fireplace that it would never catch alight, but people forget about sparks and heat transfer. Also, fireplaces and chimneys are not built the way they used to be.
The modern trend is independent units with metal flues. Perhaps checking the fireplace and chimney should be on a check list when buying a home. Insist a fire is lit to check it draws properly.
After it has been burning for a few minutes, put your head into the roof void to see if smoke is leaking. It was good to know Mike appointed a reputable company like A19 to assist him.