Help needed....

[stsmike]

Hey, I don't post here much, but I lurk often!

I have an elderly, widowed aunt who owns a house that has recently been invaded with mice. She called an exterminator who set traps and "located" how they are getting in. He told her she needed to "cement up the foundation"... So my dad and I went over to see if we could help her out.

Her house is a bit unusual as the ground level overhangs the basement (foundation) walls by a foot or so. I have only seen a few houses of this construction, so I am not very familiar with them. Basically the upper level just hangs over the foundation by a foot (see pics), and the underside of this overhang is covered by the same type of material that they use on the underside of a soffit.

We believe the mice are coming in via the underside of the overhang. There doesn't appear to be "covering" for the underside of the overhang where the rear porch meets the house (see pic).

How would we go about sealing up (and thus mice proofing) this part of the house? Flashing and spray foam? Any advise would be helpful.

Thanks, Mike

P.S. For some reason the pics are pretty low quality... I can repost them if needed. Hopefully you can see the overhang in the wide shot (with window well) and then where the porch meets the house.

 

[Majordisorder]

Remove poorly fit sheathing (if there is any) replace with precisely cut material, then cover with some type of soffit material suitable for outdoor exposure.

Yea, looks like its impossible now since there is no room to work and minimum clearance to the ground has been ignored.

 

[JoeFin]

Brick and mortar up to the existing.

 

[RPH]

Hardware cloth, may have to dig under to get access.

 

[75gmck25]

When we were trying to keep mice from getting in around some of the access holes in my house (for AC lines, etc) we covered all the areas very tightly with a wire mesh we got at Home Depot. It had about 1/4" spacing in the grid and the wire was fairly heavy duty and galvanized. I don't know if there is space to tack the mesh up under your aunt's house, but maybe you could get a small power stapler in there to put it under the "soffit" area.

Its so close to the ground that you need to put something in there that the mice cannot easily gnaw through. Standard aluminum soffit material, or strips of AC duct tin might also work if you can figure out how to tack them in place.

Bruce

 

[stsmike]

Thanks for the replies so far. The concrete from the patio extends back to meet the foundation, so I can't dig under the overhang.

JoeFin: I may end up doing so, but there will be difficult challenges. Trying to get back where the foundation is will be a challenge. Also, how would I get a good "seal" at the top where it meets the house? I guess I could get it as close as I could, then use pest resistant expanding foam to seal it up??

RPH: That would work, but I am not sure how I would affix the mesh to the underside of the house (especially where the foundation meets the overhang). There is only about 1.5" of room between the patio top and the overhang's bottom. The with of the steps is about 36" or so, therefore it is a substantial span. Any ideas?

75gmck25: Those are good ideas, but as you said it is going to be difficult due to the limited space vs. affixing them to the overhang....

Just tossing out ideas, what are some cons to trying this: Finding some lumber that will slide under the overhang, but over the patio with a little room to spare. Place either metal flashing, soffit material or a good mesh material on top of the wood and affix it to the wood. At this point I would apply some sort of sealer (silicone??) and slide the lumber under the overhang and position into place. Then I could raise the lumber to fit tightly to the bottom of the overhang and affix it via screws. To seal up any gaps I could go around the edges with rodent resistant foam? The lumber wold hopefully be sturdy enough to provide support for the cover material over the inaccessible span (behind the steps and where the foundation meets the overhang). I'm not sure how I will affix the lumber to the "left" side as it is the edge of the house with the patio extending beyond it, but for the "right" side, I could dig out the dirt enough to get a corded or cordless driver under there.

I'm still open to other ideas...

Mike

 

[xtremek]

........ covered all the areas very tightly with a wire mesh we got at Home Depot. It had about 1/4" spacing in the grid and the wire was fairly heavy duty and galvanized. .......

Bruce

This is the "Hardware Cloth" that RPH mentioned. I used a staple gun to secure 8" to the bottom of my studs so the mice wouldn't chew through the siding I used for the interior walls in my barn. How you get access, sorry but I'm no help. Maybe access from inside the house?

 

[stsmike]

xtremek: There is no "easy" access from the inside. The construction seems to be that they pour the foundation and then set the floor joists on the top of the foundation, overhanging them by 12-18". Then the house is completed as you would a normal house with the exception of a covering over the underside of the overhang. The only way to access from the inside would be to remove the floor covering and the sub-floor.

Maybe the concrete route would be best... I am still undecided. If I do decide to do concrete, I guess I would mix up small batches and pile it up as best as possible along the edge. I could then "finish" it when it has set up enough to hold shape? I would complete the job by using pest resistant expanding foam.

Mike

 

[Flivver250]

I live in farm country and mice are a reality. We have bait stations with poison, but our 2 outdoor cats work around the clock killing mice. Since the cats moved in, no more mice. I put a pet door to the shop for them to get in and sleep, no mice in shop.
Mice will find a way in no matter what, just kill them. Old fashion snap traps with peanut butter work well and elderly people should be familiar with them.