New Suspended Floor

A couple of members requested that I post some details on a new suspended floor that I completed a week a go.

This was what I found after removing the floor boards. Typical of many houses constructed between the two world wars when timber was in short supply


Removed all that sub standard timber and ran concrete pads for the new sleeper walls to sit on. Over a ton of concrete was needed

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I ran four sleep walls as I wanted my hifi to sit on the joists where they were bearing on as close as possible to the FRAIM and speaker feet. 6” x 2” C24 Joists at 600 centres


75mm of kingspan type insulation and 22mm chipboard securely glued screwed to the joists

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I managed to run the new oak strip flooring into existing finished floor level at the relevant points to within 1mm so I was more than happy


System in. 3rd 500 to go active being picked up on Tuesday


I ran the left hand speaker cables under the floor along with CAT6 Ethernet from my modem from the hallway

Mains wise. I have 4 double switchless sockets.
Two are being fed via a 4mm ring
Two are fed each via 6mm radials

I have the two 500’s in one double socket on the ring and a Chord M6 block in one of the other double sockets on the ring feeding
2 x 555ps
Supercap ( Snaxo)

My two switches are plugged into one of the double sockets on the radial

The sound is excellent and getting better by the day with so many cables ( and one of the 500’s) burning in

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Bass is noticeably tighter than in my previous room which has a floor similar to the now removed one in the new room

I appreciate that this isn’t a DIY job and not a realistic option for most of you guys with suspended floors but I was asked for an update on how I went about it


Very cool!!

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Great job. My situation. Is very different. Oak parquet tiles over i8 inches of concrete. Well at least my Rega P9 is immune from foot falls. However it makes renovation difficult and acousticly challenging.

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Great job and super attention to detail.
Hopefully you’ll never see it again. :wink: :+1:t2:


Thanks guys. I’m very impressed with the Kudos KS1 speaker cables in my system. In this room/ set up the bass is better than with the Chord Music in the old room. Very surprising and a real bonus after some of you guys reported that the bass was a little shy with the Kudos. It is such a great cable overall.

I’ve gone back to the original Burndy cables also. Again really enjoying the sound. I’m planning to use the supplied basic Naim 4pin din/XLR from Snaxo to 500’s. I tried a pair on a single 500 a few weeks ago and like what they do. Someone wrote that Naim Lavender works best with the higher level gear. My experience seems to confirm a logic in that judgement.


Can’t see any damp proof membrane? I hope you installed some or you will end up with damp drawing up the timber from the ground beneath

Don’t be insulting. I’ve been a house building and renovating Joiner all my working life. It’s on top of the concrete sleeper wall :roll_eyes:

I wasn’t, just couldn’t see it, plus i don’t know what you do.
Surprised that you have put the cement on the sides off the timber then as you have just bridged it then

IME, the nature of the underfloor conditions dictates how belt ‘n’ braces you need to be with DPMs between masonry/brick and timber/even metal e.g. in many of the Devon coastal towns, the ground is former riverbed and the local water tables can be quite high. Add this to Victorian/Edwardian builds with minimal airbricks and things like slate DPMs, and where moisture-retaining fire clinker was shovelled under the floorboards in days gone by, the recipe for damp/high moisture in sub-floors is obvious.

Worse, the clearances under the original 4’’ joists are often small, which means digging out much of the ground & clinker (not compromising shallow wall foundations), so as to enhance ventilation and allow a better timber structure to be re-installed. In extremis, underfloor fans are often recommended.

Of course, it’s always advisable to leave trap doors for plumbers and sparkies, as you never know!!