advice on lying engineered floor

[olo]

Hi all,

I would like to lay ~15mm thick engineered floor in my hall. I live upstairs and my subfloor is built from T&G floorboards which are fairly level and sound. Currently I have an underlay and laminate floor. I would also like to make the new floor a bit more soundproof. My questions are:

1) should I lay plywood or osb board directly on the floorboards to make it more stable and help with the noises from below, 6/9/12mm? 2) what sort of underlay could you recommend to maximise noise reduction, I know it's the mass that will help the most, so is it worth an investment at all? 3) I have makita circular saw, do I need any other saw (jigsaw, mitre saw) . Because it is hall, I imagine there will be a lot of cutting required (radiator pipes, doors, corners, etc) 4) any other ideas or tips?

many thanks for any suggestions,

[NT]

These floor structures are very like timber frame walls, and mostly the same noise reduction techniques apply

one method is a magic bullet, each just improves things. Each element of the construction can be tackled: the ceiling, the joists, the old floor, the new floor.

If the ceiling is plasterboard, I'd probably start by pulling up a floorboard every 18-24" and dolloping down a nice thick lump of plaster between every pair of joists to support the weak plasterboard. The dollop should go from edge to edge to maximise stiffening, and can have some sand mixed in. Then one could add 1/2 a trowel of loose sand in each of the resulting wells between the dollop bridges, mainly to provide damping.

For the old floorboard layer I'd at least make sure there are no gaps anywhere. Replacing it or adding to it with osb would help, but those are relatively costly options. 18mm chip is cheaper, but still significant cost and labour, I'd be tempted to omit any new timber.

There are various options on that link to look at, all depends how much result, cost and labour you want. Just realise the result from each measure is only so much.

NT