Installing furnace in attic (apologies for being off-topic!)

[enovikoff]

I have a 200lb furnace to install in an attic. There's a larger than necessary access hole because of other construction. I've considered winching it up but the house-of-cards-like shake roof construction isn't strong enough to carry the weight (you gotta love California!). I feel like a pyramid builder about to build a pyramid. Before I build a mud ramp, does anyone have any suggestions?

If you guys can only comment on jobs with stone or mud in them, do you know of any other forums where I could get ideas on this?

Thanks,

-eric

[JNPremodeling]

If the roof won't hold 200#, I would be more worried about next winter, when it snows(yea I know...California...but ya never know ), than getting the furnace up there. A roofing crew weighs way, WAY more than 200#, even shake roofing weighs more than that, why do you think the roof won't hold it for the amount of time you're talking about(what?, maybe an hour)? Unless you're talking about suspending it from the roof, you should be fine.

[MHI]

Most attic furnaces are installed though an access hole from the inside, such as pull down attic stairs. If you have no access from the inside, then how are you going to service or replace the unit in the future.

[JNPremodeling]

If I read it right, he's talking about winching it up from the inside through a hole in the attic floor/main floor ceiling. Problem apparently is the roof won't support 200#. Maybe I need to read again to make sure I'm taking this right.

[tilemanct]

Before you even attempt this feat, check with your local building and zoning department to find out what is required for this install. There are fire code issues. There was a homeowner here who tried to do something similar and burned down the house. No permit, no inspection, no collect on the insurance policy. Can you say bankruptcy.

[Davy]

We will have to wait for Eric to explain a little better. Maybe he means that the rafter he would need to winch from wouldn't hold 200 lbs. In this case maybe he can add a support post, a 2x4 or two would do down to the floor or maybe just to the ceiling joist. It would need to be run at an angle to keep it from being in the way. Just a guess.

[oldbob]

Suggestion #1
Two pipes, two ropes, two short 2x6, and some duct tape and two rods bent into an "L"makes the makins of a coffin hoist.
Think double "well windlass" on each long side.
Put decent size nails in edge of 2x6s for a set of shaft cradles.
Drill hole in pipe for crank to stick through.

You will need a stop rig to hold the crank.
This can be a pin through a selected hole in 2x6.

Suggestion #2
Use a sheet rock elevator.

HTH OB

[JNPremodeling]

First thing to do is read this again: (good thinkin' Tilemanct)

Before you even attempt this feat, check with your local building and zoning department to find out what is required for this install. There are fire code issues. There was a homeowner here who tried to do something similar and burned down the house. No permit, no inspection, no collect on the insurance policy. Can you say bankruptcy.

Now, I was thinkin' more about this. Why not buy a couple beers and invite a couple friends over? It's only 200#. If there's access from below, just carry it up there. (If you meet the requirements listed above)

Like the drywall jack idea too

[NVC]

What JNP said.

That's a heavy air handler, are you sure the A-coil (if air-condit.)isn't attached and can come off? Even a 5 Ton unit isn't that heavy.

But if it is, after codes/reqs are checked, grab a couple of young gorrilas before they have blown out their backs power lifting, and they'll press it up. <pops some Orudus, just thinking about it>

If it's gas, there are requirements to bring in combustion air also.

I also recommend hanging it on threaded rod with vibration dampers. I've seen them hung with strongbacks on the underside of multiple rafters so it spreads the load across the span. If A/C condensate pump, 120 power dedicated for FAU, another 120 circ. for condensate pump & required light above FAU. Need a tray with primary and secondary overflows, in case condensate pump fails.

That's all I can think of now, but the inspector will let you know if I forgot anything.

Mark

[ntexasdude]

In one of my previous lives I installed many a furnace in attics. Often times we had very little access to get the thing up there. I can recall a handful of times where we disassembled the furnace and carried it up piece by piece. Not the preferred method but sometimes the only way sans cutting a big hole in the sheetrock somewhere.

[NVC]

Robert?

Bet ya don't miss the previous attic dwelling life much, eh?

I had similar previous lives, which involved humpin' package units up stairs to the roof, on account of the boss being too cheap to get a crane. This was the same boss that I pulled cast non-hermetically sealed refridgeration compressors onto the top of grocery store roofs with a rope, and prayed for no pedestrians and rope breakage. Cheap bastage.

<Just came to the conclusion why his back is f'd up>

What doesn't kill you can only make you stronger . . . right?

Mark

[enovikoff]

I managed to do the hoisting today. The furnace is an American Standard 95% horizontal/downdraft unit, and yes it really weighs that much. I'm putting in new bathrooms and there was a section of neighboring hallway ceiling that was as yet unframed. The problem I had was that the opportune rafter (a 2x4 like all the rafters!) above the hole was too weak and cracked looking to trust. I ended up sistering another one on and adding some kickers to the adjoining walls, then using a pulley system to give me some mechanical advantage and with two muscular guys who just happened to show up, we did it. The biggest problem was that the pulley didn't quite get the heater all the way up, and that the heater needed to be supported across its entire side to prevent warping the sheet metal. I strapped the heater to a piece of plywood with a furniture dolly under it, and lifted the whole thing. After some struggle at the top, the thing was able to roll across the plywood I have as an attic floor in the equipment area, to its designated spot. It will be sitting on some vibration mounts in a pan on the floor of the attic.

Don't worry, it's all being done according to code, with inspections, and lots of TLC. There is an attic stairs for repair access, but sliding the 180lb unit along with a 200lb human pushing it up the stairs would have exceeded their rating!

It was the suggestion to build some more structure that did the trick. Thanks!

[ntexasdude]

Glad you got 'er done. BTW, a 95% American Standard gas is furnace is a nice rig. You're going to have to become a plumber and roofer to finish the install. Condensing gas furnaces require a pvc fresh air vent pipe and a pvc exhaust pipe which usually have to penetrate the roof. I installed one in my house last year.

Here's a thought. If at all possible hang the unit from the roof rafters with chains and isolation mounts. Units resting on the ceiling rafters can cause vibrations and unwanted noise even if you use a spring loaded isolation system.

And Mark, I don't miss those attic days at all. Attics can get 150° here in the summer and then you have all the dust and fiberglass and the constant fear of falling through or knocking a hole in someone's ceiling. My own attic is the only I ever intend to crawl in these days.

Oh, and like you, I've hoisted big compressors onto roofs with a rope because I worked for a cheap bastage.

[JNPremodeling]

Condensing gas furnaces require a pvc fresh air vent pipe and a pvc exhaust pipe which usually have to penetrate the roof.

Is it not possible to run this pipe out through the soffit venting or knee wall?

[ntexasdude]

Originally Posted by JNPremodeling

Is it not possible to run this pipe out through the soffit venting or knee wall?

The are 2 seperate 3" pvc pipes. One is a dedicated fresh air intake and the other is a dedicated exahsut pipe. Condensing gas furnaces exhaust cool, moist air so they use pvc plastic instead of double wall metal flue pipes. They also require a 3/4" condensate drain that runs into the sewer pipes. In an attic install you can sometimes tap into a sink or toilet vent that runs through the attic. If you have an evaporator coil attached most codes require the use of a secondary drain in case of an overflow. Typically the overflow drain runs out the soffit and drains onto the ground.

Yes, it is quite possible to run the pipes horizontally out of a side wall. Special precautions and code restrictions may apply depending on where you live and what type of building. Usually it easiest to make a roof penetration but not always. These furnaces come with detailed installation instructions which need to be followed to a tee.

Hope this helps. I'll be glad to answer further questions.