Thread: What's happening to my floorboards ?

Cheers Paul. I have ducted air con so there's multiple outlets throughout the house, do you suggest I put a couple around the house (upstairs and downstairs)? And how big of a container?

Cheers

SWMBO had some problems with her nose a couple of months ago and the question was asked by the specialist regarding home heating. We have a gas fire and he suggested that part of the problem may be dry air ie. low humidity. 45 to 50% was the desired range and he said putting a bowl of water on or near the heater wouldn’t work. Early days of water on stoves and slow combustion heaters usually worked because the water was boiling or near boiling.
He suggested a humidifier if the humidity was low. I went the whole hog and bought a humidifier without doing any measurements, Unit works by ultra sonics. The interesting point is that after setting the humidity setting to 45%, it hardly ever switches on as the room humidity is close on or over just over 45% most of the time.

Originally Posted by groeneaj

Cheers Paul. I have ducted air con so there's multiple outlets throughout the house, do you suggest I put a couple around the house (upstairs and downstairs)? And how big of a container?

Cheers

Andy

Truthfully I don't know and really I am suggesting that as a very crude stop gap measure. I think the main problem for you will be how easily you can place water near the outlets. Are they high or through the floor? Too much humidity tends to invite mould or other fungus. I think i would try with a couple of bowls first up around the size of a soup dish and see if that makes a difference. It may take a few weeks rather than waking up tomorrow morning and finding the gaps closed up. Some sort of meter to measure the actual humidity with and without water bowls might be an idea too otherwise you will head off down Lappa's track.

Regards
Paul

Originally Posted by AlexS

The ambient humidity for the last month or so has been in the 25%-40% range in our area, so it may not be all down to the aircon. Neighbour had a similar problem with a new floor. Not sure what can be done about it.

Hopefully the following will be corrected if i have it all wrong...

If the cool (cold in Andy's area) external air is at 25% (ambient) when it is brought inside a house and heated, the humidity will drop by around half for each 10 degree increase in temperature. (this correlation is approximate as I could only find a comparison expressed in degrees Fahrenheit).
So if Andy has been heating 5 degree air at 30% to 25 degrees, the the relative humidity inside his house would be around 8%.

One test of how dry the air actually is, is to look for dry cracking skin on your feet and hands.

I wonder if treating the floor with a wood stabilizer containing PEG/PPG or some similar HMW polymer solution may help limit the movement. Something like this: Polyethylene Glycol (PEG) Green Wood Stabilizer | Rockler Woodworking and Hardware

Ian, the principle is correct, not sure about the numbers without checking. I suspect the ambient humidity at Andy's is higher than 25% when it's that at my place.
I bought a cheap digital hygrometer from a pet supply place - people who keep snakes use them. It's useful to have in the workshop.

Thanks Alex

Just to extend the numbers, if Andy's external air is at 60% and 0°, then after heating to near 30°, the RH would be around 10-15%, which is still very dry.

numbers for degrees centigrade would be nice if anyone has them -- BobL?

Originally Posted by ian

....if Andy's external air is at 60% and 0°, then after heating to near 30°, the RH would be around 10-15%, which is still very dry..

Pretty rare for it to get down to 0° up here (often close though) let alone at Winmalee (elevation there is a modest 260m compared to 1017m here), and even then that would be usually after midnight, perhaps getting on for dawn (when the AC is probably not running).

As far as RH is concerned, I have no accurate measurements at all, but I think I read in this thread that 40-45% is about normal? If that is the case then as an eyeball figure it might have been perhaps 20-30% up here for most of the last few months? Maybe it was a little higher at Hawksbury Heights.

Another "eyeball" observation is that we had very few frosts here this year, and this could be for one of two reasons. It felt like a warmer than usual winter, but there was bugger all humidity in the air to drop out as frost. Not really even many heavy dews. Possibly a combo of both factors.

Edit: I think I recall reading that it was the warmest winter on record here (and many other places)

I concur with Paul. Shrinkage due to drying and yes AC could be a definife factor

DaveTTC
The Turning Cowboy
Turning Wood Into Art

Originally Posted by FenceFurniture

Pretty rare for it to get down to 0° up here (often close though) let alone at Winmalee (elevation there is a modest 260m compared to 1017m here), and even then that would be usually after midnight, perhaps getting on for dawn (when the AC is probably not running).

As far as RH is concerned, I have no accurate measurements at all, but I think I read in this thread that 40-45% is about normal? If that is the case then as an eyeball figure it might have been perhaps 20-30% up here for most of the last few months? Maybe it was a little higher at Hawksbury Heights.

Another "eyeball" observation is that we had very few frosts here this year, and this could be for one of two reasons. It felt like a warmer than usual winter, but there was bugger all humidity in the air to drop out as frost. Not really even many heavy dews. Possibly a combo of both factors.

60% and 0° are merely examples to demonstrate the effect of raising the temperature inside Andy's house.

If the outside air was at 30%, the inside air would be at around 7% after raising its temperature by 20°.

Anyway you look at it, anything less than about 20% is very dry.


Unfortunately I can't offer a solution as here in Canada, the humidifier is built into the air con unit and you set the RH along with the temperature. .

One possible solution for you is to sand that beautiful gloss finish off the boards - right back to bare timber - and then finish with an oil or wax finish. If you can remove the edge gluing then the boards will still shrink and expand but the gaps between the boards will open and close rather than splitting the boards. If you don't want to remove the finish you could try to find a way of cutting through the edge gluing from the finish. The floor won't be as pretty, and not as smooth, but the boards themselves will be less likely to split.

Good luck

David

Thanks for all the replies, some really helpful posts. I think the first thing to do is buy a Thermometer-Hygrometer and get some initial readings of the moisture levels in my house. Then I'll look at some basic solutions such as the water in a container, then look at a humidifier for a permanent fix.

Cheers

I've had one of these in my workshop for the past 5 years or so - does humidity, indoor temp, and outdoor temp (via a remote sensor). Also stores min/max humidity and temperature over time (until min/max readings are reset). I think this brand came from Dick Smith (now defunct), but Jaycar would probably have something similar

20171005_160942_resized.jpg

It'll be interesting to see what your indoor humidity does over a 24 hour cycle with A/C.

Just on the matter of humidity, I made a batch of boxes over the last month, when the humidity ranged from mid-20s to low 30s. They are simple boxes with a drop-in lid. I thought I'd allowed enough for expansion, but today, with the humidity at 56%, the lids all had to have their edges trimmed. I'm hoping I've left enough for when they get sent to the tropics, which is always a possibility.