Best method for sealing a mortar joint between concrete sill

[Thedreamer]

Can anybody help with how best to seal a mortar joint on a concrete sill?

 

Is it best to use a sealant out of the tube (if so which?) or should I apply SBR bond on top of the joint. 

 

I also plan to paint the sills in the next few weeks.

 

Any help would be greatly appreciated.

[bassanclan]

Not sure why you would be sealing the joint. Either the mortar is ok and keeping the water out, or it needs raking out and repointing

[Carrerahill]

11 minutes ago, Thedreamer said:

Can anybody help with how best to seal a mortar joint on a concrete sill?

 

Is it best to use a sealant out of the tube (if so which?) or should I apply SBR bond on top of the joint. 

 

I also plan to paint the sills in the next few weeks.

 

Any help would be greatly appreciated.

I assume you have a joint in a sill, and as is typical moisture will pass down through mortar so a waterproof seal is what you seek?

 

I would use Silicone 825 or EB25. 

Edited October 11, 2019 by Carrerahill

[Thedreamer]

1 minute ago, Carrerahill said:

I assume you have a joint in a sill, and as is typical moisture will pass down through mortar so a waterproof seal is what you seek?

 

I would use Silicone 825 or EB25. 

 

Yes, that is what I'm after.

 

I will look out for that, Silicone EB25 is basically a better version?

 

Also would you put a bead down and then get it as flat as possible so goes a bit beyond the joint?

 

 

 

 

 

 

 

[Thedreamer]

9 minutes ago, bassanclan said:

Not sure why you would be sealing the joint. Either the mortar is ok and keeping the water out, or it needs raking out and repointing

 

No that is not what is required here. I don't believe that mortar ever provides a waterproof seal.

[Carrerahill]

44 minutes ago, Thedreamer said:

 

Yes, that is what I'm after.

 

I will look out for that, Silicone EB25 is basically a better version?

 

Also would you put a bead down and then get it as flat as possible so goes a bit beyond the joint?

 

 

 

 

 

 

 

I think 825 is good - get it in Toolstation - it is specifically for this sort of thing. EB25 is probably a bit sales gimmicky. 

 

https://www.everbuild.co.uk/product/silicone-825/

[Russell griffiths]

Silicon 825 cannot be painted over. ,!!

[Thedreamer]

10 minutes ago, Russell griffiths said:

Silicon 825 cannot be painted over. ,!!

 

I went to my building merchant and the only colour they had in 825 was anthracite, which just so happens is what I'm intending to paint the sills.

 

@Carrerahill thanks for this. ?

[Carrerahill]

2 hours ago, Russell griffiths said:

Silicon 825 cannot be painted over. ,!!

Puraflex 40 if you need to paint over it @Thedreamer

 

I use that for my car restorations and love it - it's a brilliant, polyurethane based product that can be used to stick stuff on, seal things (inc. areas that will be subject to oil and fuel).