Using House in Winter for First Time this year (re: crawl space and water pipes)

I have a house near a local lake. The house is built on raised 4X4 posts and has wooden lattice covering the underside of the house where the water pipes are located (CPVC). It’s on the side of a hill, so one side of the house is hardly six inches off of the ground, but the other side is about four feet of open space.

Normally we only use the house in the summer, and in the winter, we drain the pipes and otherwise shut it down.

This year, we will use the house all winter. I’m wondering what the best way is to heat/cover/do whatever to the underside of the house so that the water pipes don’t freeze and burst. Thanks.

That sounds a lot like the house I grew up in. It was originally purchased as a summer home and eventually became our primary residence. I believe my dad had a heater of some sort underneath the house for winters.

From the time I was old enough to use a hacksaw every spring was hell before he got the heater. We would have to crawl underneath the house to replace sections of broken pipe. Not fun.

That sounds like me in the spring when I forget to drain a section of line. :slight_smile:

But is there a way to do what I’m trying without a hard covering? Maybe put a couple of vents from the heating unit under the house?

This is likely the only winter we will stay here and after this winter it will go back to being a summer-only home, so if I can half-ass it cheaply with good assurance that it won’t crack the pipes, I would like that way.

If it is going to cost a lot of money anyways, I’d rather do it right.

The heating vent idea might work, and depending on how your house is heated, that may keep the pipes from freezing up by itself(but I wouldn’t recommend trying that out). I’ll probably end up talking to my dad today and can ask him about it. He’d know better than me since he lived there a lot longer after I moved out.

How cold is it? Where is it located?

It’s located in West Virginia. A couple times per year it gets in the teens, sometimes single digits. Below zero maybe a day or two every few years.

I wouldn’t use heating ducts as you will be blowing warm air outside which creates a negative pressure inside, This will cause outside air, or even musty air from the now positive pressured crawlspace to enter the home.

I have a somewhat simular setup and use heat tape (electric resistance heating tape made for wrapping pipes) and pipe insulation around that. If you go this route make sure the heat tape is in firm contact with the pipe along the length (wrap it tightly).

Some people use a electric space heater if the area is small enough and you can contain it, some even a lightbulb (don’t use a CF bulb - they are useless even for this purpose).

And finally, just for greater assurance in very cold weather leave a faucet dripping

Oh yeah, and good luck - that helps too :slight_smile:

Thanks. Just to be clear, your pipes are exposed to the outside air? (underneath the heat tape and insulation)?

There is a windbreak with some venting so it is ‘dark’ there but no insulation, very thin walls and the bottom of the house is insulated from the crawlspace.
A bit better then your setup as it is enclosed. I would recommend trying to create a enclosed space under the house around the pipes if it is practical, if not the entire crawlspace.

Update: I’m thinking of enclosing the crawl space with that 4 X 8 polysty-something type of insulation that gives an R-3 value. Along with that, I’ll use the wire that keeps heat on the water pipes. My heat ducts are double insulated.

What say you experts? Am I looking at a winter of freezing pipes, a freezing house and thousands of dollars worth of electric bills? The house is about 750 sq. ft…

putting heating tape on the pipes and covering (with insulation) the total exposed pipe is important. enclosing the crawlspace with a windbreak, with areas that could be removed for ventilation in warm weather, would be good. insulating the crawlspace if you aren’t actually heating it might not give desired results because it might also keep it cold.

Should I put a small electric heater down there when it gets freezing cold?

750 sf is kitchen, bath and laundry rooms at most. With luck the builder kept them together to save money on plumbing. The heat tape and pipe insulation is the way to go. A space heater won’t work unless you close the crawl space. Even then you are inviting other creatures to join you for the winter. Some can be most unpleasant.

Pay attention to the heat cable load. There is a maximum length you can use on any given circuit

You also need to keep the tub/shower drain from freezing. It will freeze in the P trap. Put a cup of RV antifreeze down the drain before bed.

Follow up question here kanicbird. What are your heating bills like? Is the house comfortable in the winter?

Do you have any idea what the wall insulation is like? Crawlspace pipes are not the only ones that can freeze. If you turn down your heat at night, I’d recommend leaving your sink cupboard doors open on nights when the temps get below freezing.

supplying heat might be OK in a well pit (volume of a small closet). for the whole crawl space you would just be wasting heat.

insulate the floor or use lots of rugs, it will be cold.

drain traps below the floor should have heat tape on or have a low watt heater (small appliance light bulb) in an insulated box.

Just wrapping the lattice in plastic will probably get you by. So long as there are no drafts blowing through the ground temperature and the heat coming off the house will keep temperatures above freezing. Heating tape is extra insurance and a good idea on the drain pipe.

Plenty of people in mobile homes get do fine with just the plastic in New England.

An added question is where do you get your water from?

Wall insulation is R-13. Attic insulation is R-19. Not up to Energy Department specs, but pretty good nonetheless. No insulation in the crawl space, and I honestly don’t think I could get to the back half of the house without digging. The space goes from 6 feet high to about 7 inches high. Plus there’s duct work, wires, pipes and all kinds of stuff going everywhere. I nixed the insulation idea straight off.

I’m considering plastic for 1/2 of the house on the high side, and using spray foam for any obviously open areas. I get my water from a well about 30 feet from the house. The well is in a pit and is brought to the surface by a submersible pump. The feed to the house is underground until it enters the crawl space where it is exposed for about 3 feet. (I say exposed, but it is encased in an outer pipe). I plan on running the heat tape that extra three feet out there, covering the pipe.

Here’s my overall question, though. I’ve lived in an uninsulated house before in the winter. It’s freezing balls cold and the heat runs all of the time. You freeze and the electric bills are outrageous. I want to eliminate that as much as possible in my situation with a reasonable cost. Plus I don’t want the pipes to freeze. Thanks again for everyone’s help.

I’d caution against sealing a crawlspace tightly with insulation. Moisture buildup will cause mold. I open my foundation vents in the summer and close only for the two coldest winter month.

Viny siding is a great option for older uninsulated houses. They install a special foam board first and then do the siding. Or you can have insulation blown into the stud cavities. Thay means drilling holes. But, the vinyl siding covers that up.

My grandmother used electrical heat tapes under her house. They work great. Get a timer and set them to run dusk to just after dawn.

Heating tapes will go bad after a few winters. At the start of winter it’s always a good idea to turn them on and feel them. Confirm they are getting warm.

One final question. I’m 3/4 ths of the way done with tacking the plastic, and I’m impressed by my handiwork. The remaining part of the house has only 7 inches of clearance to get to the sides of the wall. Unless I lose approximately 110 pounds within the next two hours, there is absolutely no way in hell that I can access that portion of the house. My only other option would be to tack the plastic to the OUTSIDE of the lattice making the house look only slightly less attractive than if I vomited on it.

So, my final question, can I just leave that 7 inches (approximately 30 linear feet) open to the elements this winter, or should I bite the bullet and tack the ugly plastic?

ETA: There are no water pipes in this isolated corner.