Rats, rats, rats and exterior insulation
Rats, rats, rats and exterior insulation
I live in the greater Boston area where we have a massive rat infestation. That’s putting it lightly. I’m currently building a 24 x 24 1/2 story ADU with cross Gable roofs. Given my tight lot restrictions, I plan to have only spray foam for the roof and the walls It will have a full basement that’s 4 feet below grade and 5 feet above grade all concrete. I know 5 feet concrete above grade seems overkill, but it’s better than rats in my house? I have had rats eat our cars several times and I’ve had rats tunnel under our 5 foot foundation of the principal structure and into our basement.
Give my circumstances, having under slab insulation and exterior insulation seems hazardous? If I were to have exterior insulation and under slab insulation, it seems like mineral wall would be my best option? Or does it make the most sense to just have everything on the interior? Or given l my trauma with dealing with the rats, I’m overthinking the situation?
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After moving into our current home about six years ago we realized we had a rat problem. Rats in the crawl space, rats in the attic, rats in the ...
We did not want to go the poison route. Neighbors who do end up with regular quarterly or annual visits to top up the poison and haul off the remains. So we searched for an alternative and found this company. While it was initially expensive, once the job was completed we have not had any more problems. They sealed everything, trapped the critters, came back to check the traps and removal. For example they added heavy metal mesh to each and every crawl space "vent". They checked again until no more. We also cut down trees too close to the house that allowed rats to climb to the roof.
Jack Russell Wildlife Control https://www.animalproblem.com/gallery
Their statement says it all:
"The problem is that if industry standard building practices took pests into consideration, I wouldn’t have a job. Industry standards aren’t good enough for effective wildlife control. The knowledge of the animal’s capabilities is what sets me apart from these guys. I take nothing on faith or the manufacturers assurances. I have seen what otters and raccoons can rip through, and what mice and bats can squeeze through. All Jack Russell repairs are guaranteed, otter strong, and mouse tight, and we will find all the holes, no matter how hidden they are."
I also do not like the idea of poison, not only is it in effective, I’ve seen it work it way up the food chain. So it make sense to keep all this in mind and secure any penetration as best as I can while I build.
Thank you
Rats,
This is one of those things where I agree the consequences of infestations make doing things that would otherwise seem overkill worth it. I have battled rats in my sister's early 20th century home for decades, and each time they come back is devastatingly disruptive.
A bomb-proof solution? 1/2" galvanized hardware cloth under the sub-slab foam, and depending on your appetite, on top of the sheathing on the half height framed knee-walls above the concrete. Keep all the rigid foam on the interior.
Thank you Malcom. It seems like it’s become one of the daily woes of living here as my city has hired a “Rat Czar” to head the battle. I will do as you suggest! I do appreciate your help, I wasn’t actually planning on having a half height knee wall and was doing all concrete for piece of mind, but with your method of mesh over the knee wall, it sounds bulletproof proof enough and will save me a chunk of change on concrete.
Rats,
Good luck. Better dealing with them now than later!