Three-year-old loft conversion suddenly very noisy

[Bert Coules]

Just over three years ago I had a major loft conversion done on my semi-detached sixties bungalow: the process included removing and replacing all the existing ground floor ceilings and building above them with a timber carcass and new roof.

As expected, everything took a while to settle and establish itself and there was some evidence of a small amount of movement, most noticeable in the fit of a couple of sliding doors. But before long everything was fine.

Then in the last few weeks, the new ceilings/loft area floors suddenly became startlingly noisy, emitting what I can best describe as intermittent sharp (and loud) cracks. Since this mostly happens towards evening I'm inclined to put it down to expansion and contraction, though there are also isolated incidents of it during the day.

Am I right? And if so, why is it happening now? And should I be concerned?

Many thanks.

[Tricky Dicky]

That does not sound good, do you live in a former mining area or is the area prone to sink holes. Some creaking is not usually an issue but loud cracks suggest further investigation is needed?

Richard

[Bert Coules]

Thanks for your thoughts. No to the mining area and sink holes question. If there was something serious happening I would have expected it to be evident visually: cracks in plaster, displacement of the plasterboard panels in the downstairs ceilings, something on those lines - but there's nothing (at least nothing so far).

[Brian Gaff (Sofa]

Yes is the bungalow built on a concrete raft over an old clay quarry? There is a house not far from me like that and the raft is beginning to crack, one assumes due to subsidence under it, the road outside has also developed cracks and a definite dip, and the porch fell off a couple of years ago. How long are such fixes supposed to last I wonder, these were put up in the

1960s. Brian

[Bert Coules]

It's certainly on a raft and underlying it is - I think - mainly stony clay with some shingle. Not a quarry, though. As far as I know, this area used to be open fields.

That's very reassuring! If the noises continue I'll get someone in (maybe a structural surveyor?) to advise.

Thanks.

[Fredxx]

If there are no obvious signs of moving through cracks or any other signs I would put it down to thermal expansion.

Where I am the property seems to be alive, mainly in the evening when everything is cooling down.

Just keep an eye out for any changes.

[NY]

Don't talk me about mining subsidence. My school in Wakefield was right under where the Coal Board wanted dig new tunnels to mine a new seam. This is back in the days when we *had* mines - "You remember them? Dinosaurs, dodos, miners." (Brassed Off).

The Coal Board knew that there might be subsidence, so they dug a six-foot deep trench in the grounds all round the perimeter of the buildings, filled it with ash (how many bonfires did that take?) and tarmacked it over. This was supposed to make sure the whole school dropped/twisted as a single unit, as if it were on a raft. Right load of old bollocks that was! For the rest of the time I was there, the front of the school was propped up by an enormous wooden buttress, and there was scaffolding and planks that you had to clamber over when going up and down the main staircase. There were cracks (some 1/2" wide) in the plaster all over the place. Goodness knows how much the school got in compensation because the so-called subsidence prevention trench hadn't worked. My friend's house, just down the road from the school, also developed nasty cracks and the family were put up in a hotel for several months while the Coal Board did remedial work.

Still, it was probably cheaper than what the Coal Board paid British Rail to divert the East Coast Main Line between Selby and York because of the subsidence that the Selby Coalfield mine was expected to cause. I'm not sure whether there *was* much subsidence to buildings in the area, but it was wise to take precautions and BR benefited by the removal from the main-line route of the notorious reverse curve north of Selby station and the even more notorious swing bridge over the Ouse.

[Theo]

There might be something you can do in terms of fixing some cheap laser pointers (firmly) to the structure, and marking out where the beams land. Then go at different times of day and see if there's any difference. (turning them off when not in use, obviously!)

(I'm not sure laser pointers are collimated enough, but worth a try before going for anything fancier)

Theo

[NY]

And take care not to look into the beam accidentally...

[alan_m]

CH pipes in loft or under the floor of extensions.

Central heating now cycling in shorter times now that the weather is warmer (or more likely CH switching off as the sun shines through windows providing more solar heating)

[Clive Arthur]

If you have any small cracks, glueing microscope slides across them is a good way to check for movement. You can pick up a pack of these on eBay for notalot.

[NY]

I've always wondered how effective it is to glue a glass slide over a crack. It depends rather critically on the bond between the glue and the glass being stronger than the glass itself - otherwise as the wall moves, it breaks the glue/glass bond (or the glue/wall bond) and the slide remains intact.

[The Natural Philosopher]

Even that is as helpful

[Robin]

With something so important I'd prefer a measure which avoids the false alarm of a glass slide broken without developing movement - eg

[NY]

Assuming you can *see* that the glue joint has failed. Not as easy to spot at a glance as a crack across the glass.

[Spike]

We've had a very long dry spell, with occasional very dry winds. I suspect that the timbers are drying out to a level they haven't seen before and shrinking in the process, leading to some unusual noises. Try drying your laundry indoors...

[HVS]

On 14 Apr 2021, NY wrote

I know this is a diy group, but isn't thisi a case where using proper crack-monitoring tell-tales would be better than making you own?

Cheers, Harvey

[HVS]

On 14 Apr 2021, Robin wrote

+1 (I've just posted a similar comment -- I should've read ahead....)

Cheers, Harvey

[Andrew]

Your school was underground ??. Amazing !.

[NY]

Haha. The perils of writing a sentence one way round, then changing it round and forgetting to change all the other references.