Sill

[Alwayslearning22]

Hi does anyone have any idea why there’s a gap underneath my back door sill? There’s no mortar it’s just been left open, is it a movement gap or something? 
Could I fill this with expanding foam and silicone? 
thanks 

Edited May 4, 2022 by Alwayslearning22

[Alwayslearning22]

[tonyshouse]

Mortar for me 

[joe90]

8 minutes ago, tonyshouse said:

Mortar for me 

+1 pushed well in to support the door sill.

[Simplysimon]

would do both, low expansion foam to the back with mortar to the front. have you given the spiders notice to quit as they'll need time to find a new home?

[tonyshouse]

I wouldn’t but you can, we will never know 

[Iceverge]

One side expansion foam and the other half mortar.

 

Then report back to the forum after a thorough test! 

 

[Alwayslearning22]

Thank you for the replies. I read somewhere that timber frames need Differential movement joints at door openings and window openings.

( i also have gaps underneath one of my window sills) 

Is this actually a done thing? 

[tonyshouse]

Yes but it shouldn’t be, windows often on packers should get sealant on the outside as a minimum 

 

door sills should not be unsupported