Filling a Gap

[Avenger]

I need some help, some advise on what to do about this gap.

I recently purchased a new home and moved. The new home has a HUGE shop. It's large partially because at one point, the lean to was walled in and insulated. However, I noticed this gap along the back wall of the lean to. You can see some daylight coming through. Simply looks like the person/people who built the wall didn't measure correctly, didn't care, or there was something there at some point that is not there now. Or, the building or concrete moved. Either way, there is a gap.

I'd like to fill this gap before winter. I'm concerned about drafts and critters coming in from the cold. This lean to portion of the shop is going to be my reloading room/brewery/man cave section. The gap runs the entire length of the back wall, about 20 feet. What should I do about this? How should I fil this gap? I considered expanding foam out of one of those spray cans. Foam backer rod and caulk? Would the mice eat through that? Pressure treated lumber butted up against it? I can't really get to the backside of this wall easily. There are planter boxes and a dog kennel right in the way. What are your thoughts? What would you do if this was your shop and your gap?

 

[D&D]

Preferably window and door foam or gaps and cracks foam.

 

[RSR]

Is the existing board straight/level?

If so, this would be my approach (as mice are a major problem where I live).

1) Push metal mesh screen back into the gap (tougher for critters to chew through).

2) Fill with rodent-resistant expanding foam (the green stuff - they regularly chew through the normal yellow stuff where I live).

3) Butt a board up against the existing one to cover the gap. I would both screw/nail it to the board, and use some type of adhesive/caulk to also secure/seal it to the face of the concrete surface.

 

[jay3534]

Second on RSR's suggestion

 

[dstig1]

Another vote for RSR's suggestion with the one further suggestion that steel wool may be a better rodent barrier to pack in first, rather than mesh. Might be hard to get any mesh in there effectively.

 

[ponytug]

Another vote for @RSR's suggestions.

I use the copper plated mesh, then foam. The copper plated version doesn't rust, and rodents really avoid it for some reason.

All the best,

Peter

 

[Rockbadchild]

Spray foam not the window seal one it doesn't expand as much as the crack and gap one, caulking on top for a nice finish, could cover it with a plank if you like ... how wide is the crack ? looks like 1/4 inch or so, if so critter wouldn't be able to get in very far to chew it and even then I personally haven't seen critter using that stuff for their nest not.