What's the best way to lag pipes?

foam pipe lagging. I only did mine in areas which may have been vulnerable to frost, against an external wall, for example.

cable tie them on.

cost/benefit analysis, work out the cost and payback time. your call

RT

The best way is to feed the pipe through them as you install it, so you don't have to split the foam sleeve afterwards. If you do split it, it has a tendancy over time to open up at the split. You can get some plastic staple like things you push in along the split to stop it doing this, but I don't know how effective they are. It does follow swept bends OK (at least when you don't split it). I tended to cut the pieces slightly too long so that it is in compression when installed. I see lots of installations where it's shrunk leaving bits of pipe exposed, and mine hasn't done this (yet, anyway).

For central heating, I believe it is only required to insulate where the pipework passes through unheated areas, like under a suspended ground floor, but not for example between a floor and ceiling of two heated areas. I also insulated it where any electricity cables were in close proximity, but that was more to protect the cables from heat. This can also be a good idea where it's near a cold water supply pipe, so you don't turn on the cold tap and find it runs warm for several seconds. Part L also requires insulation of the pipes connecting to the hot water cylinder, if you have one.

I bought my insulation from Wickes who had it going cheap at the time as part of one of the energy saving initiatives. I believe the foam you need is the type with the wall thickness same as the pipe diameter. There is some much thicker stuff too, but thats rather more for preventing outdoor and loft cold water pipes freezing in winter. You might consider that for the pipework in your garage if it's not heated, but ISTR it was much more expensive.

You can get a sort of metallised bubble wrap in about 50mm width for pipe lagging, from the usual online suspects, but it's a bit pricey. However Wickes (and no doubt others) do the same(?) stuff in about 600mm width which would probably be cheaper and possibly easier to use.

Put the foam on a straight bit of pipe near the curve, glue it together, then slide it over the bend when the glue has dried. If it's an elbow rather than a bend you can mitre the sleeve.

There's more expensive flexible stuff. I'd use that for tightly flowed bends and use the cheaper semi-rigid stuff for straights, lightly flowed bends and elbows.

Christian.

Hi,

What sort of per m price were they charging, and what dia/thickness?

cheers, Pete.

Bends you can bend the foam and wrap with duct tape etc.

No real need to insulate inside 'warm spaces'.

In studowork, pack glass fibre rockwool all around.