A 130mm thick internal block wall,, in a kitchen has a shallow vertical chase - about 1.5mt, into which 22mm copper pipe has been placed. There are no joins in this length of pipe.
This will sit behind a kitchen cabinet 715mm, and then beneath 500mm of tiling.
The surface of the copper pipe is just below the face of the wall it sits in.
It was advised to wrap the pipe in something protective by the gas engineer, prior to filling with a wall filler, 1000 gauge DPM has been used, and tape run along the joins, the DPM is like a sleeve, rather than tape applied direct to the pipe.
The gas engineer has tested the pipe OK, and left, he will be back in a few weeks for another job at the site.
Over the gas pipe I have asked the builder to place metal capping (cut down resilient bar has been used as traditional wiring capping is too thin, in my opinion).
The builder though, rather than fill with filler, has used expanding foam, with the metal flush with the surface.
I understand that sleeved gas pipes should be open one end, but feel the expanding foam will have expanded around the flexible DPM sleeve to remove any air gaps, which from my understanding will be a good thing. The end of the pipe before it goes into the chase has been left exposed, the space behind the cabinet will also be alllowed to vent.
Guidance for pipes in walls - either recommends the pipe be encased in Dot and Dab filler, or encased in wood battens, where the wall is plasterboarded, but the wood battens would surely leave a small gap around the pipes, and then the gap sealed up.
My understanding of Foam around copper is that it is not harmfull or corrosive in any way.
If the builder had used filler, it would have been difficultto get it round the back on the pipe, and voids might have been created, albeit very very small ones, is it the large voids that the Regs are most concerned with ? and how is Expoandnig foam viewed if used in such a way.
I will ask the gas engineer his opinion, of which he will no doubt have, but also good to aks others 'on the job' here.
This will sit behind a kitchen cabinet 715mm, and then beneath 500mm of tiling.
The surface of the copper pipe is just below the face of the wall it sits in.
It was advised to wrap the pipe in something protective by the gas engineer, prior to filling with a wall filler, 1000 gauge DPM has been used, and tape run along the joins, the DPM is like a sleeve, rather than tape applied direct to the pipe.
The gas engineer has tested the pipe OK, and left, he will be back in a few weeks for another job at the site.
Over the gas pipe I have asked the builder to place metal capping (cut down resilient bar has been used as traditional wiring capping is too thin, in my opinion).
The builder though, rather than fill with filler, has used expanding foam, with the metal flush with the surface.
I understand that sleeved gas pipes should be open one end, but feel the expanding foam will have expanded around the flexible DPM sleeve to remove any air gaps, which from my understanding will be a good thing. The end of the pipe before it goes into the chase has been left exposed, the space behind the cabinet will also be alllowed to vent.
Guidance for pipes in walls - either recommends the pipe be encased in Dot and Dab filler, or encased in wood battens, where the wall is plasterboarded, but the wood battens would surely leave a small gap around the pipes, and then the gap sealed up.
My understanding of Foam around copper is that it is not harmfull or corrosive in any way.
If the builder had used filler, it would have been difficultto get it round the back on the pipe, and voids might have been created, albeit very very small ones, is it the large voids that the Regs are most concerned with ? and how is Expoandnig foam viewed if used in such a way.
I will ask the gas engineer his opinion, of which he will no doubt have, but also good to aks others 'on the job' here.