[DianaKaye]

So we bought this house about 2 1/2 years ago. There was an empty rat trap in the attic and also a hole identified, so we thought we would be good with a little work. We fixed the hole and still had the rodent. Put poison in the attic and rodent now gone. Took poison out and it seems like we have some mice there that we hear occasionally, not all the time. We had a couple contractors out for critter removal. The first quote was over $4,000 and included rodent removal and fixing all the locations that they were getting in, plus giving us a warranty for one year. There was also one place in the house structure that they wouldn't warrant. He also talked about a "contractor's void" - a place that contractor's typically don't fix along the roof line and where rodents get in. For this, he recommended a fine wire mesh. The second company that came out was very small, looked over the house, never gave us a quote and said he couldn't give us a warranty.
So I have all these questions:
1 - What is a contractor's void and is it common? I wasn't here when he came and didn't see it.
2. Is there some poison to use that doesn't have any secondary poisoning effects (such as those animals that eat the poisoned mouse)/
3. As we need to call more companies for this work, is there anything in particular we should ask or look for?
Anything else you can add will be greatly appreciated. Thanks!

 

[DoomsDave]

YOW $4 grand sounds awful high.

For starters, I'd keep looking.

And, I'd sure try to do your own.

Use regular mouse traps, as well as rat traps, baited with unhomogenized peanut butter. That gets them, no residuals.

I wouldn't use those glue traps. One, they're sadistic, you can hear the poor rodent caught and stuck in it squeaking in terror, so unless you're a sadist . . . Two, you can't reuse them.

Poisons as you note, do have their problems. Here in California, we have mountain lions that are more likely to die from the long-term residual effects of anti-coagulant rodent killers than anything except getting hit by a car or truck.

A side benefit is that in the course of doing it, you will learn something.

And, cats can be great rodent killers, too.

 

[PatentPending]

Does your attic have a floor, or is it loose-fill insulation?

For the former, you might be able to get by with bait/trap/whatever, but if you've got rodents nesting in insulation, that's a nightmare probably best left to a pro.

$4K seems high, though.

Not sure what a "contractor's void" is either...

 

[Chris616]

We had a rat problem in the attic when we moved in which did not look that bad when we did the house inspection. I've learned now that with a truss construction house (no usable attic, so the insulation lies on top of the ceiling drywall), the evidence is mostly hidden under the insulation where it is warm in the winter. The biggest issue was the rats gnawing the insulation on electrical wires and foam air sealing around electrical boxes. Obviously, gnawing wire insulation down to the conductors creates the potential for short circuits and sparks to happen. It would be worthwhile having a look at your attic wiring.

I have not heard the phrase “contractor’s void”. I can’t understand how the first contractor’s warranty would work. Presumably the warranty means that if rodents return within a year they’ll rid your house of them at no cost. If they say that one part of the house is not warrantied, though, doesn’t that give them an “out” to say that is probably where the rodents are getting in?

We set traps and put out poison, but the bait was untouched and the traps not tripped. Rats are pretty smart. I think that they just decided that this was going to be a dangerous place to stay. Then we sealed things up to prevent a reoccurrence. Searching for and sealing places where rodents can get in isn’t rocket science. Nor is setting traps. We did all that ourselves. I guessed that it would be expensive.

Chris

 

[ChuckF.]

"Contractor's void", also called the contractor's gap, is where the roof sheathing coming down at an angle, doesn't mate up with the outdoor fascia. You can generally see it from a dark attic, a long strip of light. It happens because to close it up effectively would require a full-length angled edge on the fascia, and builders generally chose not to do that, perhaps because years ago it would have been a very difficult cut to make.

Now builders generally put a piece of gutter flashing along there, and on an older house the first time the shingles or gutters get replaced, they put up the flashing. Newer codes may require the flashing.

 

[DianaKaye]

Out of curiosity, how do you like someone's thread?

Our house was built in 1946 and has 2 additions on it. There are 2 areas that have an attic and the insulation in on the bottom. That's where the rodents appear to be.

How does unhomogenized peanut butter work better than the other? FYI, we have a barn on the property with livestock and haven't been successful in getting rid of the rats. We tried the 5-gallon tub trick and caught 3 in 5-months time, they wouldn't touch snap traps (even when baited a month and not set). They do eat the poison which I'm not thrilled about. Needless to say, I was incredibly happy when the snakes moved in.
@Chris616 How did you search for places where rodents can get in? I understand mice can get through a dime-sized area and rats a quarter-sized area. It's not overwhelmingly bad, but we need to fix it. My neighbor had squirrels in her attic and a fire started as they were chewing on electrical wires. Unfortunately, she wasn't able to live in her house for about 7 months.
@ChuckF Thanks for the insight into the contractor's void. The $4K contractor offered to put a mesh there. I was a little surprised by that as I could just envision a rat chewing through the mesh. Flashing sounds a lot sturdier. So part of our roof has an attic and the other half/three--fourths doesn't.

This whole thing is really interesting and will take some money/work to fix. Thanks!

 

[SeniorSitizen]

Have a barn, livestock and no Calico barn cat? Unheard of.:biggrin2:And if Gophers are problematic she'll take care of those too.

 

[DianaKaye]

@SeniorSitizen, Wow! You could make money off her. Great photo!

 

[DoomsDave]

"Contractor's void", also called the contractor's gap, is where the roof sheathing coming down at an angle, doesn't mate up with the outdoor fascia. You can generally see it from a dark attic, a long strip of light. It happens because to close it up effectively would require a full-length angled edge on the fascia, and builders generally chose not to do that, perhaps because years ago it would have been a very difficult cut to make.

Now builders generally put a piece of gutter flashing along there, and on an older house the first time the shingles or gutters get replaced, they put up the flashing. Newer codes may require the flashing.

Thanks for the definition!

Hmm. In my case, the Contractor's void is the one between my ears . . . .

Can't seem to get nuttin' right. :vs_cool:

 

[DoomsDave]

Out of curiosity, how do you like someone's thread?

Our house was built in 1946 and has 2 additions on it. There are 2 areas that have an attic and the insulation in on the bottom. That's where the rodents appear to be.

How does unhomogenized peanut butter work better than the other? FYI, we have a barn on the property with livestock and haven't been successful in getting rid of the rats. We tried the 5-gallon tub trick and caught 3 in 5-months time, they wouldn't touch snap traps (even when baited a month and not set). They do eat the poison which I'm not thrilled about. Needless to say, I was incredibly happy when the snakes moved in.

@Chris616 How did you search for places where rodents can get in? I understand mice can get through a dime-sized area and rats a quarter-sized area. It's not overwhelmingly bad, but we need to fix it. My neighbor had squirrels in her attic and a fire started as they were chewing on electrical wires. Unfortunately, she wasn't able to live in her house for about 7 months.

@ChuckF Thanks for the insight into the contractor's void. The $4K contractor offered to put a mesh there. I was a little surprised by that as I could just envision a rat chewing through the mesh. Flashing sounds a lot sturdier. So part of our roof has an attic and the other half/three--fourths doesn't.

This whole thing is really interesting and will take some money/work to fix. Thanks!

Supposedly the non-hom peanut butter has a stronger smell, which draws the rodents better.

Yeah, the rats do get wise after a while. I caught a lot, but the damage to some of my potted palms from other rats persists.

YOU HAVE A BARN!

That changes things, alas, completely. I hate to say this, and hope someone can prove me wrong, but barns are perfect homes for rodents. Accept that you'll have them, even with a small army of barn cats. Unless you turn it into a house . .. .

You'll have better luck keeping them out of your house.

 

[Chris616]

@Chris616 How did you search for places where rodents can get in? I understand mice can get through a dime-sized area and rats a quarter-sized area. It's not overwhelmingly bad, but we need to fix it. My neighbor had squirrels in her attic and a fire started as they were chewing on electrical wires. Unfortunately, she wasn't able to live in her house for about 7 months.

We went up on the roof, into the attic and around the perimeter of the house and methodically looked at everything with the question “Could a rat get through that?”. In the attic it was useful to be in the dark and look for any place where we could see light. We found two places where the rats had got into the attic. Your situation will be different, but just to illustrate examples…

The first entry point were the plastic attic ventilation vents on the roof. They have a molded in grill to hopefully keep things out, but on close inspection we could see that one had been chewed through. For most of these we stapled heavy wire mesh (hardware cloth) over the opening in the plywood roof sheathing from underneath, in the attic. One vent is in a cathedral ceiling where we can't access the underside, so until I am ready to replace the vent I’ve tucked rolled up hardware cloth under the edges of the vent against the shingles. That still allows it to do its job of letting air out.

One other point of entry was fairly obvious. The rats had chewed the rubber weatherstripping along the bottom of the door of the attached garage where there was a dip in the concrete allowing them to squeeze under the door. From there they were able to get up the walls into the unfinished ceiling and through the common soffit to the attic of the house. I’ve retrofitted some formidable looking hardware cloth to the bottom of the door to prevent a recurrence.

The soffit of the house is cedar boards, so there were a few places where knots had dropped out, so we’ve sealed those up. As part of our whole house renovation we replaced three small plumbing vents (the black pipes projecting through the roof) with one 4” pipe. I imagined what it would be like if a rat went in there and died, so I soldered a piece of hardware cloth over the lead cap that covers the pipe. That was about everything that we did.

I (or more importantly, my wife) do not ever want to clean up a rat nest in the attic again, so I go up there every six months to inspect for the telltale droppings. I keep baited rat traps up there, but as I said earlier I don’t really expect to catch anything in them. Knock on wood it’s been six years rat free so far.

Between rats in the attic, a mouse infestation in the basement, arsenic in our well water and radon gas in our house I hope that we’ve dealt with all the big issues by now...

Chris

 

[Old Thomas]

Have a barn, livestock and no Calico barn cat? Unheard of.:biggrin2:And if Gophers are problematic she'll take care of those too.

Female cats are the best hunters and calico cats (3 color cats) are always female.

 

[DianaKaye]

Wow! Thanks everyone for the tremendous help! Hopefully, we can get this done within the next couple months. :smile: