New Suspended Floor

About 50 years ago, my dad was rewiring their bungalow and sent my younger brother down through one of these trap doors into the large crawl space below. He was supposed to crawl about 25 feet to the far end of the room and then “cut the large cable” with the wire cutters he had taken with him.

When he got there, for whatever reason, he was full of caution, not a common occurrence it has to be said. Anyway he called back a few times and dad got increasingly exasperated “just cut the large cable”, meaning the old 2.5 T&E of course.

Anyway my brother said “do you mean the large cable or the medium-sized cable?” It turned out the unbeknown to dad there was a cooker cable, still switched on, also running through that void. Fortunately nothing was done until this was fully explored and my brother therefore lived to tell the tale!


Oh yes, always expect the unexpected! My sparky was very happy when asked to do a 100% re-wire, on the basis he could ‘kill the board’ and rip-out, as there were so many strange connections and spurs, both internally and externally (in non-externally rated cabling!). Same with a 100% re-plumbing which needed doing.

Good post. I actually removed the pointed up mortar from the wall plate that my bricklayer left on before fitting the insulation but I would ALWAYS fit 100mm DPC under the timber plate even with an under floor like mine which is very dry and well ventilated.

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Suspended floors are horrible for hifi. There’s only a 2ft gap under my suspended floor and it took me a lot of effort to build a brick base for my hifi and speakers to sit on, whilst leaving the boards alone. The difference in sound was very large. If I had gone to all the trouble to remove the suspended floor boards, it would have been a doddle to build a brick base. To do all that work and then stick your hifi back on a wooden floor is a crime.

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Solid Floor = No Problem…?

Yes, very sensible indeed! What I don’t understand is why no houses I have ever have had have been built with such things, nor easy access to in-wall toilet cisterns, shower valves etc! I do as much work as I can myself, and with everything I always have the thought how my excess it when sometime in the future, whether next year or 25 years’ time, something needs leasing or servicing. I’m working on a sums house at moment, and instilling that thought into him it seems successfully!).

With electrics, these days it is very limited as to what regulations allow you to do yourself, but the maxim is absolutely always, always check yourself that the power has been turned off on the circuit you are working off – never rely on somebody else - AND use a suitable tester to verify at the remote point before doing anything that’s may expose you to a live conductor, whether that be cutting a cable or anything else - and if not possible to do that, e.g. if cable disappearing into wall both ends, then even if you’ve turned of the entire house power do make absolutely sure you use insulated tools (should be anyway) and keep clear when you cut.

Not necessarily. Badly built, bouncy suspended floors, yes, and a lot of those have been built over the last century or so. A well constructed one should be fine.

No. They’re awful. I’m right.

The classic forum answer applies ‘it depends’ e.g. going back to the 1950s and 60s (even 70s), solid concrete floors were in vogue, often with a reinforced plate (rebar) covered by a sharp sand/cement screed, this often somewhere 50mm+ thick (min nowadays =75mm). These often delaminate and settle badly – and can cause damp issues, especially where CH pipes were sunk in undressed (who knew copper and concrete/cement would react!?).

Plus, plate movement is common, as is the emergence of voids due to ground movement. IIRC, plates were often poured over a bed of aggregate/mini-peers.

Nowadays, newer houses have ground floors with hardened insulation (e.g. Jablite) , over which is a screed, often with CH piping for underfloor heating. So, the floor isn’t 100% solid, albeit close in general understandings.

…and then someone like me comes along and puts a floating wood floor on top :scream:


My house was built new in 2005. The downstairs floors are certainly concrete - but its likely that they are not ‘solid’. More likely concrete beams with screed on top.

If new in 2005, I’d expect insulated floors with screed, with parquet/wood as the finishing? I’ll have to check as IIRC the regs for floor insulation in new builds changed in the 1990s(?).

I cannot agree. I’ve had poor acoustics in rooms with bouncy floors in the past, but also very good acoustics in rooms with suspended floors that were well constructed and rigid. The room I’m using now, for example, has by far the best acoustics of any room I’ve used despite being a 1st floor room, therefore with a traditional suspended floor. The last 3 rooms I used before that all had solid floors and appaling acoustics. I would suggest that in general, the effect of room dimensions far outweigh that of construction materials in their effect on acoustics.

Thats likely. But with carpet… :crazy_face:

In a friend’s local 1990’s build (good quality by all the looks) which is carpeted, you can feel the ‘not small’ wiring conduits as you walk across the floor i.e. it appears these weren’t covered in the screed, just set in :thinking:

There are always trade-offs – and, thinking about it more, this is quite a clever way of accommodating changes and re-wires, as you don’t want to be messing with stud/dry-lined walls – although the latest diktats of having sockets higher-up the walls can complicate this.

You can’t agree, because you think you’re dealing with the general public. You’re not.

I have suspended floors in the two rooms housing my hifi. Both floors are pretty well made. My hifi is in one room and I built a brick base up under the floorboards. I cut 6" square cutouts where the stand spikes are and they directly sit on marble solidly cemented on the brick. The difference was immediately obvious.

I liked it so much, I did the same thing for my speakers in the listening room. The Shahinian Hawks sit on 12" polished marble plinths, again directly cemented to the bricks. The difference was additionally obvious and big. This project was posted years ago here and Shahinian were very interested in my results.

I can very easily demonstrate the speaker difference by simply lifting the speaker off these plinths and placing on the suspended floor. The hifi stands are obviously not as quick to demonstrate, but anyone who understands about hifi wouldn’t question such a simple bit of logic anyway.

It’s nothing about room acoustics, it’s about minimising vibrations and losses of fine details through the speaker cone movement.

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I am hoping that you meant - ‘the latest regulations’. That is what they are.

I have sockets higher up the walls - and like them. Easier. Better.

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Amazing what you can accomplish in an afternoon. :grin:

I would expect a solid floor to be distinctly preferable to suspended, no mattef how good the latter. The first 7 houses I owned, built variously between 1818 and mid 1980s had solid floors, and presented no hifi problems. A couple of bedsits rented between houses had suspended floors, with which the biggest problem was bouncing TT. My present house, built in 1970s, has a suspended floor, and although II no longer have a turntable it is the first to give problems with the hifi requiring complete layout reassessment. But whilst the suspended floor might not be ideal, I think it was the room shape not floor that caused the problems.

Hopefully the OPs suspenders will do a solid job for the hifi.

Sorry open goal. :wink:


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