Installation of flue through concrete slab

HI there,
I have recently purchased a wood burning standalone fieplace with a stainless steel flue. Because my house is double storeyed it needs to be fitted though a cement slab. How easy will this be and what tools are required to make a hole in the slab?
Thanks for any (good) advice.
--
Sue Trott


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Wow, I never saw a residence with concrete slab floors. They are usually found in industrial or commercial buildings.
If you want to cut a rectangle, an abrasive blade in a circular saw will work for a couple of inches thickness.
Another method is to use a masonry bit and drill a series of hoes, they chip out between them. Keep in mind, there is probably steel in there too.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Typically, some kind of jack hammer, or hammer drill to get through the cement. Floors like this are guaranteed to have some kind of steel reinforcing rods "rebar". The rebar can either be rough and molded into the concrete, or in tubes and tensioned later.
I don't have the experience to know if this is safe, cutting cement floor. Can you go out the side wall, elbow, and up the side of the building?
Christopher A. Young Learn more about Jesus www.lds.org .
HI there,
I have recently purchased a wood burning standalone fieplace with a stainless steel flue. Because my house is double storeyed it needs to be fitted though a cement slab. How easy will this be and what tools are required to make a hole in the slab? Thanks for any (good) advice.
--
Sue Trott



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

For the size of the hole that you need it may pay to hire a concrete cutting and drilling company to diamond drill a nice round hole through the concrete with little mess and dust. As said above, there will be steel in the concrete, re-bars can be OK, but be cautioned about cutting any tensioning cables as that could be a problem. It may take an engineer to identify what you have, it they can without opening something up to check it out, and possibly identify where you can drill to avoid the tension cables.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Some years ago, I heard a story that was spooky, in how true it could be. A couple fire department guys were visiting a building site. Being friendly, and helpful. Hope it didn't catch fire, but wanted to know what's going on, just in case.
The fire department guy noticed all the wood cribbing, and frame to hold up the cement floors. Looks, and sees that it's post (post "afterward", not like fence post) tensioned concrete. He asks if they have post tensioned the concrete, yet.
The construction workers looked blank. And then said no, we havn't gotten around to that. We're too busy jacking the cables.
When sky scrapers are built, often the floors are held up by wooden frames. If the wood catches fire, and burns away, the building will collapse. That's important fo the fire department guys to know.
Christopher A. Young Learn more about Jesus www.lds.org .
For the size of the hole that you need it may pay to hire a concrete cutting and drilling company to diamond drill a nice round hole through the concrete with little mess and dust. As said above, there will be steel in the concrete, re-bars can be OK, but be cautioned about cutting any tensioning cables as that could be a problem. It may take an engineer to identify what you have, it they can without opening something up to check it out, and possibly identify where you can drill to avoid the tension cables.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Ed Pawlowski wrote:

Many of the new homes being built in my city (SW-Ontario) have the first-floor being made of concrete (and naturally there is also a full basement as well). I would guess that the second-story floor is conventional wood framing.
Having a concrete floor gives you the ability to use various stains or acid-etch combined with urethane sealer to create a stunning finished surface, similar to polished marble.
The OP doesn't say if his fireplace is in the basement or the main floor. I don't know how common it is to have a house with a second-story floor made of concrete.
There are circular hole-cutters for concrete, but I don't know how large they can get (at least up to 4" I know).
The OP might want to duct the flue out the wall to the outside (if the stove is not in the basement that is).
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

First of all I am not an expert but we did just finish a house that required a section of basement floor to be cut to accommodate some plumbing mods - after we moved in.
Find someone with a concrete saw who can do the job for you. It was a dirty and smelly job that done pretty quickly. My guy cut about a 18" x 36" square through concrete and rebar in about 20 minutes. I set up a couple of fans to exhaust as much of the exhaust fumes as possible, but we were all feeling pretty "good" before it was over with. We draped plastic around the work site but some of the concrete dust still got out - but not terrible. After sawing, he finished getting some of the edges out with a small sledge.
You might also want to talk to a plumber or heating contractor about clearances. I suspect, since concrete transfers heat fairly well, that you want to leave space between the flue and the concrete. We installed a wood burning insert in our house and the manufacturer provided pretty good clearance data of the unit and venting.
I would NOT use a jack hammer.
RonB
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I noticed a couple guys jumped in while I was writing. If your slab is pre-stressed cables are a good concern. Again, talk to a plumber or building contractor. The plumber that did our job had a hand-held sonar set that allowed him to see the plumbing, rebar and other stuff before he got started.
RonB
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

*Unless your entire structure is masonry I think it is unlikely that the floor is solid concrete. Usually they pour 1.5" of lightweight concrete on top of the plywood base to get the fire rating needed. If that is the case, the concrete will be soft and very easy to break up.
If it is in fact solid concrete, you should get a concrete cutting company to come in and make the hole. You don't want to cause damage to the physical structure and there could be utilities such as water or electric encased in the concrete in addition to the rebar reinforcement.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This requires a building permit and (hereabouts, at least) much free engineering advice is available from the permit staff.
--
Don Phillipson
Carlsbad Springs
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You need to hire pros who will pull a permit and do the job right, to code. The last thing anybody needs is a bungled amateur project that could cause more problems than you could anticipate. Experienced concrete workers have the tools and knowledge needed. A two-story fireplace vent is well past handyman capabilities.
Joe
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You mean like those pros I see on Homes show on TV? The ones that screw it all up, take your money and leave? Also, just because someone is an experienced concrete worker doesn't mean they know anything about chimneys.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.