Pipe Insulation in the Loft

[stem]

When I insulated the pipes in my loft, I carefully covered them completely. I mitered the insulation at the elbows and included any isolation valves.

Some years ago we had a single story extension built and I noticed last weekend that in the extension roof space, only the straights are insulated. The elbows and isolation valves are exposed. (In some places the pipes are below the roof insulation, but not everywhere) In addition, where the heating pipes run along one wall on saddles they are so close to the wall, that only space for very thin insulation to be fitted between the pipe and the wall. Also the saddles are not covered.

Is this normal practice?
Do bends / isolation valves not run the risk of bursting if they freeze?
Does this meet building regulation because of the heat being lost for example?
Should there be a minimum specification of thickness for the insulation in an unheated roof space?

 

[PrenticeBoyofDerry]

Both hot and cold water pipes should be thermally insulated within the loft space.
The reasons being twofold:
*To offer frost protection
*To prevent undue warming
If isolation/service valves are along the route of the pipework, then the fitting should be insulated but the the isolation mechanism accessible.
One way of complying would be by using valves were levers are left accessible but body of fitting covered.
And there is a minimum requirement of insulation values required, dependant on pipe sizes.

 

[SimonH2]

Some years ago we had a single story extension built and I noticed last weekend that in the extension roof space, only the straights are insulated. The elbows and isolation valves are exposed.
...
Is this normal practice?

Yes, because doing it properly takes time, and most customers don't want to pay for that.

It's not correct, but it's fairly normal practice for probably the majority of the trade for the reason given.