Is Solvent weld pipe into pushfit boss adaptor OK?

[MortarThePoint]

Can you use a solvent weld (SW) pipes in the pushfit (PF) boss adaptors used on the soil stack? The adaptors come in 32mm, 40mm and 50mm sizes so is it the same answer for all? As SW outer diameter (OD) is larger for each I guess there is an element of if you can get it in its OK as long as the BCO is then not going to have a problem.

Second question is to if making a solvent weld joint between the boss adaptor (PVC-U) and pipe (ABS) it is a mix of materials. Does that work OK for the weld and is standard?

 

Basic stuff, but if you don't know you don't know. I do know you mustn't mix SW and PF pipe and fittings normally and you have to use an adaptor if you want to.

 

Pipe        SW OD    PF OD  

32mm    36mm     35mm

40mm    41mm     40mm

32mm    56mm     53.5mm

Numbers from Floplast website drawings

Edited September 7, 2023 by MortarThePoint

[markc]

Danger with pushing an oversized pipe into a sealing ring/boss/gland is potential leaks due to fully compressing the convolutions and potential splits and tears. The seals are designed to allow some movement and allow the pipe to ‘float’ around the centreline.

solvent is best kept to similar materials, adhesive for bonding different materials

[Thorfun]

18 minutes ago, markc said:

Danger with pushing an oversized pipe into a sealing ring/boss/gland is potential leaks due to fully compressing the convolutions and potential splits and tears. The seals are designed to allow some movement and allow the pipe to ‘float’ around the centreline.

solvent is best kept to similar materials, adhesive for bonding different materials

I think I might’ve f****d up here. At the end of a SW waste run I’ve got a PF boss adapter and have pushed the SW pipe in to it. I’ve tested and there’s no leaks but it will be boxed in so access at a later date will be troublesome. As the PF boss adaptor has been solvent welded to the boss I can’t just swap it out. 
 

should I leave it as is or cut the SW pipe and couple it to a PF pipe using a suitable coupler and then push fit into the PF boss adapter? Or is there another potential solution?

[MortarThePoint]

12 minutes ago, Thorfun said:

I think I might’ve f****d up here.

 

I have spoke to both Floplast and Wavin (OSMA) and they both say that all their pushfit boss adapters (e.g. SP11 or 2S399) are designed to be used with either pushfit pipe or solvent weld pipe. I shared the same concern as @markc, but it seems to be fine.

 

Floplast and Wavin (OSMA) also both said that it is OK to solvent weld ABS pipe into their PVC-U bosses (in the case of OSMA that may require an ABS solvent weld coupler as the boss is the same ID as the pipe). I queried that the materials are different, but both said it was fine. I was surprised.

 

I think I feel more comfortable using the pushfit boss adaptors onto the stack as I am a bit of a commitment-phobe.

[Conor]

Virtually all of my branch connections are solvent weld into 40mm rubber bosses. They're called universal for a reason

 

[markc]

14 minutes ago, Thorfun said:

I think I might’ve f****d up here. At the end of a SW waste run I’ve got a PF boss adapter and have pushed the SW pipe in to it. I’ve tested and there’s no leaks but it will be boxed in so access at a later date will be troublesome. As the PF boss adaptor has been solvent welded to the boss I can’t just swap it out. 
 

should I leave it as is or cut the SW pipe and couple it to a PF pipe using a suitable coupler and then push fit into the PF boss adapter? Or is there another potential solution?

Morning, as it’s boxed in I’m taking it as inside so I wouldn’t worry about it, outside where pipes expand and contract you do see movement and older buildings often have no chambers or inspection points so Down pipes can back up and that’s when you need the seals to work. In your case you are just looking for it to stop odours rather than backed up water and Sh1t

[Thorfun]

29 minutes ago, MortarThePoint said:

 

I have spoke to both Floplast and Wavin (OSMA) and they both say that all their pushfit boss adapters (e.g. SP11 or 2S399) are designed to be used with either pushfit pipe or solvent weld pipe. I shared the same concern as @markc, but it seems to be fine.

 

Floplast and Wavin (OSMA) also both said that it is OK to solvent weld ABS pipe into their PVC-U bosses (in the case of OSMA that may require an ABS solvent weld coupler as the boss is the same ID as the pipe). I queried that the materials are different, but both said it was fine. I was surprised.

 

I think I feel more comfortable using the pushfit boss adaptors onto the stack as I am a bit of a commitment-phobe.

 

29 minutes ago, Conor said:

Virtually all of my branch connections are solvent weld into 40mm rubber bosses. They're called universal for a reason

 

 

28 minutes ago, markc said:

Morning, as it’s boxed in I’m taking it as inside so I wouldn’t worry about it, outside where pipes expand and contract you do see movement and older buildings often have no chambers or inspection points so Down pipes can back up and that’s when you need the seals to work. In your case you are just looking for it to stop odours rather than backed up water and Sh1t

Thanks all. One less thing to worry about!!

[Pocster]

2 hours ago, Thorfun said:

I think I might’ve f****d up here. At the end of a SW waste run I’ve got a PF boss adapter and have pushed the SW pipe in to it. I’ve tested and there’s no leaks but it will be boxed in so access at a later date will be troublesome. As the PF boss adaptor has been solvent welded to the boss I can’t just swap it out. 
 

should I leave it as is or cut the SW pipe and couple it to a PF pipe using a suitable coupler and then push fit into the PF boss adapter? Or is there another potential solution?

Could smear structural sealant around it . Allows for flexibility and water proof . You’ll sleep better if you’ve done that …

[Thorfun]

8 minutes ago, Pocster said:

Could smear structural sealant around it . Allows for flexibility and water proof . You’ll sleep better if you’ve done that …

Link?

[Pocster]

4 minutes ago, Thorfun said:

Link?

https://www.dortechdirect.co.uk/catalog/product/view/id/1815.html?gclid=CjwKCAjw6eWnBhAKEiwADpnw9vj97_W40b8ish1cfq_YwpXQ758r82RfNise3dcJy4sGJqibCyn7AhoCUGMQAvD_BwE
 

This is what I use for structural glazing ! . But the fact it’s water proof and flexible is my point I.e it’s not designed for the job you require - but can’t see why it wouldn’t work . 🤔🫤😃

[Thorfun]

1 hour ago, Pocster said:

https://www.dortechdirect.co.uk/catalog/product/view/id/1815.html?gclid=CjwKCAjw6eWnBhAKEiwADpnw9vj97_W40b8ish1cfq_YwpXQ758r82RfNise3dcJy4sGJqibCyn7AhoCUGMQAvD_BwE
 

This is what I use for structural glazing ! . But the fact it’s water proof and flexible is my point I.e it’s not designed for the job you require - but can’t see why it wouldn’t work . 🤔🫤😃

Cheers. Will bare it in mind 

[Pocster]

17 minutes ago, Thorfun said:

Cheers. Will bare it in mind 

No you won’t ! 😂