Underfloor heating pros / cons

[hellymedic]

Just about all the piano merchants I know are unanimous in their condemnation of UFH…
Anyway, it’s not usually a bathroom issue.

I would be very cautious about installing it in a large lounge...

[Wowbagger]

It's possible to buy insulated mats to stop the warm air rising directly to the underside of the piano. It's very much a humidity thing. It was required as part of the 5-year guarantee on my 1936 s/h Bluthner that I kept the humidity above 50%. There have been quite a few occasions on which it's fallen below that, but not by much. Bluthners are also reputed to be very stable.

I'm afraid my son's piano is doomed though: his ASHP heating in Finland keeps the house warm enough, but when it's -20°C outside, the humidity inside drops to <10%. My Good Pal Penelope's sister had a similar problem when she exported their family piano to Toronto. It just fell to bits.

[hellymedic]

Interesting!
We’re working on maintaining the humidity for D’s piano BELOW 50% (40-50%) and the dehumidifier is working HARD much of the time...

[Feanor]

What is the technical reason for this?

Is the frame which holds the strings under tension not made from cast metal, so not too fussed about humidity?
The pretty woodwork would be mostly cosmetic, no?

Just curious.

[Wowbagger]

The soundboard is wooden in the vast majority of pianos, as is the wrest plank, aka pinblock. The pins that are turned to tune the notes are always embedded in wood.

[Wowbagger]

https://www.robertspianos.com/piano-advice/guarantee-humidity/

Roberts' Pianos guarantee.

[Feanor]

OK, interesting.

The soundboard is simply a resonator, amplifying the frequency it is stimulated by, and does not (and cannot) modify the frequency (pitch), so is not related to tuning.
But the pinblock is interesting, because it does.

Why are the pins embedded in dead vegetables and not in the cast metal?

[Wowbagger]

I don't know the answer to that I'm afraid.

Because it's always been done that way?

I've written a whole load of stuff about this in the "Old Pianos" thread.

https://yacf.co.uk/forum/index.php?topic=41112.0

[Asterix, the former Gaul.]

We had it installed by a  pro in our kitchen.  The installation was done badly as the pro was supposed to have an assistant who didn't turn up and the work was done by one man in the same timescale.

We decided to have a new kitchen after a few years and I ripped up the badly tiled floor and UFH and re-did it using the same scheme with new materials.  It's quite a challenge using mats (like electric blankets) because the wire cannot be broken and re-joined, also the spacing rules must be observed (something the original installer had failed to do).  Nevertheless we managed ok and the floor has given nearly five years of good service.  Topps tiles was our provider - they also gave us the name of the first installer but made it clear they did not make recommendations and we know why now.  We don't keep our piano in the kitchen so that wasn't a problem.

[mrcharly-YHT]

The future for pianos is carbon fibre.

[Feanor]

I'm wondering of the wood serves to provide some level of acoustic isolation between one string and the next, to reduce any parasitic excitation.

[hellymedic]

The future for pianos is carbon fibre.

D’s Kawai is part carbon fibre & part wood.
Piano keys stick less now humidity has been reduced, on the tuner’s advice.

[Cudzoziemiec]

Tubeless castors and hydraulic pedals.

[fruitcake]

Anyway... moving away from pianos, and back to UFH...

A friend recently had it installed in a kitchen and loves it. She bought the system from Topps Tiles two years ago. The tiler installed the whole kit and the floor tiles.

More plus points:

• it saved space in the room because radiator placement became less important - in fact she chose not to have a radiator
• the sensation of a warm floor underfoot is very pleasant, and will be particularly so in a bathroom
• this type of system could be considered an ethical choice - most of the time, electricity is a lower carbon fuel than gas and its carbon intensity is reducing as more solar and wind generation is deployed
• if you (or a future owner) get a smart meter and choose a smart tariff, you could charge up the floor at zero cost at times when there is lots of renewable energy on the grid. Your electricity supplier would send you text messages to alert you to these opportunities
• electric UFH plays nicely with solar photovoltaic - and future solar PV may be compatible with apartments

Minus points:

• the control unit needs to go on the wall, and this requires chiselling of plaster for the cable plus redecoration unless it's hollow wall
• electricity is an expensive fuel at current prices, so the system would need to be used sparingly
• the interfaces on the cheapo thermostat/timers that come with these kits can be poorly designed and difficult to use *

Interesting points:

• the UFH element is laid only where there is no permanent furniture (it would not go beneath the bath / toilet) and this may prevent you from rearranging the room (moving the bath etc) in future unless you wish to abandon the UFH system at that stage

* The control unit on the model my friend bought is difficult to fathom: it was set for her but when my friend wanted a boost she just overrode the program to run continuously and the UFH ran full time for a few weeks - the electricity bill will have been large that month

[Feanor]

I have electric UFH in the bathroom, under the tiles.
It does produce a nice warm-to-the feet thing.

But it's not a replacement for a radiator / towel rail for space heating. It doesn't generate enough heat for that.
Downstairs, we have wet UFH set into the concrete pad of an extension, and that *does* produce enough heat for space heating.

[Sergeant Pluck]

Very useful, fruitcake and Feanor, although I have enjoyed the pianistic diversion. Thank you.

Work starts tomorrow. <gulp>

[Sergeant Pluck]

It turns out that there is 50mm of screed on top of a concrete base.