Hot answers tagged

12

The blower doesn't go in the attic. The hose and the control cable do. If you took the blower up there you'd also have to carry the insulation up after it. If you don't have enough hose, request an extension. Leave the blower in your truck or on your trailer unless you can't park near the door or window nearest the attic access point.


11

You don't put blow in above the door. Use batts or cut several layers poly board insulation to mimic slightly less than your attic cover. 4-5 layers will give you good coverage. This will not provide a perfect barrier but is the recommended way of handling attic openings.bb


11

I live in Florida too so I know exactly what you mean about hot attics. I had the same problem except for the pvc water pipes. I put up a number of 2 by 8 feet of 3/4 inch plywood on the rafters. Where it was possible to move over some of the cables, I did it. where I couldn't move them, I took some 2x4's, notched them for the wires to go thru and put them ...


9

OK for the most part these do not go in attics, but can. As long as you have a pretty good attic opening you can fit these in there and I have had to in two story homes - or deal with a mess. In no way am I advocating putting these in attics as a norm but I have done it a couple times with no issues. There were pros/cons - on each that I did it there ...


5

Add the cellulose right on top, I have seen folks remove the old but this is crazy both materials are insulation and combined the provide a higher R value. I would caution if all the moisture issues are not taken care of cellulose will pick up moisture and hold it longer than fiberglass.


5

Not functional, but cost. Roofs have slopes to drain water and slough snow. It's the nature of their design that there's a hollow below. Since the finished space is relatively small, and since it costs more to build a floor robust enough to carry people and furniture, and since it costs more to finish the space and insulate and add (larger) windows, and ...


5

As mentioned in a comment, those are not listed to be used for electrical cables. If you are just running one cable in one run, just use regular NM cable staples like these: If you are running multiple cables and would like to save some time, you can use "stackers" like these: If you added another 2x4 to the side of the members that run perpendicular to ...


4

If you want future-proof, run conduit You simply need to comply with conduit rules, which can be a bit tricky since it's not normal to run cables through conduit. Four cables (circuits) per conduit, no more. It's a pain to pull it through. Individual THHN wires are much easier, but you're not allowed to unjacket cable to run it through conduit. (the ...


4

This sounds like an issue from a physical damage standpoint While the NM cable only needs to be protected by guard strips if it's within 6' of a scuttle hole in your case, as per NEC 320.23(A) (referred to by NEC 334.23): (A) Cables Run Across the Top of Floor Joists. Where run across the top of floor joists, or within 2.1 m (7 ft) of the floor or ...


4

That duct is not done properly notice how the duct is collapsed. Webbing can be used I have used plumbers tape (a metal strip with holes) at the first support after a rise I will screw a saddle of scrap ductwork to keep the duct from collapsing. I have used webbing but always think it will separate over time I usually melt the holes to reduce the chance of ...


3

If your ductwork is in an uncontrolled environment, you truly should insulate it. This for the reasons you list - to help prevent vapor from becoming water prematurely. While it is not necessarily a lot, any is bad since gravity pulls it right back down the pipe into the ceiling, or the fan, etc. If your air column is smooth, the work necessary to move it ...


3

The Code says it cannot be vented into the attic or crawl space. (See ICC M1507, 2017 edition.)


3

I see lots of houses of that same vintage. You do see some houses built with unfinished attics, no floors, no fixed stairs, but not many. In cold climates you see lots of house styles that incorporated the attic space beneath the sloped roof as living space - adding dormers, knee walls, etc. - Craftsman style houses, Cape Cod style, etc. I think you see ...


3

Probably fine as far as weight goes. But I would not nail it, I would use construction screws (aka "deck screws") Pounding nails into the sides of those rafters may disturb your roof sheeting nails and or shingles, leading to leaks.


3

In the 60’s all the roofing I put down we used roofing felt 90 lb per roll. Some people call tar paper it is heavy and black and makes a good barrier. I would be guessing since we don’t know what your original vent system was or is now, but with some homes we did just prior to my knees saying no more roof jobs we had to add vents or a complete ridge vent ...


2

I used insulated flex ducting like below for my bath vents. Try to keep it flat or sloping toward the outside to avoid condensation pockets. https://www.homedepot.com/p/Master-Flow-4-in-x-12-ft-Insulated-Flexible-Duct-R6-Silver-Jacket-F6IFD4X144/203420974 Edit 1: I'm not familiar with a code that requires rigid ducting for bathroom fans. (Mass local here) ...


2

Whatever gave you the idea that blown fiberglass is substantially less effective than batts? Though the R-value of batts is 25-30% better, you simply account for that with increased depth. The inadvertent gaps and voids that batts will leave you with after fitting around countless roof framing members surely negate any benefit versus simply adding more ...


2

When I replaced a closed box recirculating bath fan with a large exhaust fan, I let the local hardware store owner convince me it was adequate to vent the bath fan into the attic because (he said) “the ridge vent would adequately exhaust all the bathroom air.” BIGGEST MISTAKE WE EVER MADE. By the dry winter season our ceilings all separated from the tops of ...


2

Yes, you can do as you describe. There's no need to double the cross blocks, as the span is short and the only real weight on the truncated joist is the drywall, which partially carries itself across the gap. Just be sure to nail the cut joists into the cross blocks well. Yes, normally attic accesses are built parallel to the trusses. There's no cutting ...


2

The squirrel cage fan relies on velocity, not pressure, to move air. A near elbow stops the momentum and reduces airflow rate. If you need 90 degrees close to the fan, put 2 90s together and swivel the joints to make it into 2 45s. Down the path a 90 elbow is fine. If the run is long or has many bends, use a double 45 or try to keep the path as straight as ...


2

I still consider it a gambrel. The word simply means "leg" or "forked leg", describing the interior supporting timbers. The inherent flaw in the design as you've shown it is potential lack of rigidity at the upper angles. Unless they're robustly gusseted there and at the lower angles they're in danger of inverting at those points. There isn't enough arch to ...


2

Romex 1 and 2 are using backstabs, which is not a good idea for other reasons. The backstab is simply connected to the screw nearest it, internal to the device. It's supposed to be an "either-or", but some people like to use it to splice the 2 wires together. It would be the same as if the two wires were joined at a wire nut, with a pigtail from there ...


2

I would add more fiberglass insulation to the top of what you already have as it will not compress as much as cellulose does. But if you have clumpy fiberglass insulation in your attic now, you may want to check it with a moisture meter before adding anything on top of it. Also, cellulose is a dusty product, whereas fiberglass blows in pretty clean. I've ...


2

Your insulation should cover the top plate of the wall. This gives you a complete thermal envelope. Covering the wall cavities will help keep cold air from coming up to the upper areas.


2

Because back then, people weren't so obsessed with "finishing out". Not only did they leave the attics unimproved, they left the basements unimproved! Can you imagine!? Real estate market prices and speculation were not beyond insane like they are today. Flipping wasn't really a thing. AirBnB didn't exist. There wasn't a mad dash to turn every possible ...


2

No sealant is required but the cutout for the box needs to be tight (not a large oversized hole) the cover plate makes the seal. The lights usually have a trim ring that seals any small gaps between the fixture.


2

I don't think the one I rented was that heavy, but it was not something I would want to carry up a ladder, nor would it have fit through the 20" attic access. Tips: They are fast. I was able to pick up the unit, and with my stepson feeding the machine we did 1000 sq ft attic adding another foot of cellulose to the existing 6" of fiberglass in an afternoon....


2

Before you add insulation, consider air sealing your attic, meaning use a closed cell foam to seal penetrations in ceiling such as top plates, holes for electrical, lighting and plumbing. This will prevent air communication between the attic and the conditioned space something that just adding blown in insulation cannot do. If you are experiencing comfort ...


2

Around here (California) all of the roofing contractors are installing solar powered attic vents, the ones where the solar panel is part of the fan assembly. No wiring and yes, they only work on sunny days, but that's the only time you really need them!


2

When I've replaced motors in the past I replace with the exact part if you went with that approach you shouldn't have to worry about clearances but it would be painful to work within that constrained space. It doesn't look like this fan is designed for serviceability from the inside but there are a lot of things like that so it doesn't surprise me that ...


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