How do we cut a hole in a concrete chimney to add a thimble into an existing flue?

[ebinmaine 67,266]

We've removed the entire oil heat system from the basement and we want to put a small decorative but functional wood stove up in the great room on the first floor.

We need to cut a hole in the chimney which is concrete blocks and likely a clay liner.

 

How would one go about doing this?

 

 

[rjg854 11,349]

It would be a slow process, but a series of drilled holes around the circumference of the thimble you want to use would help keep the damage to a minimum so that you could then chisel out the hole to insert the thimble. Of course depending on the thickness of the block would make for the length of the bit you would need. An SDS drill or a rotary hammer would also make a big difference. 

[WHNJ701 4,165]

are there any saw cutting/core drillers by you.  we hire them occasionally if we need a hole drilled into manhole for storm pipes saves us time having them drill a 12 or 18 hole for pipe

[Burnerman 758]

The liner is the problem. The tile is very hard. What are you venting? 2 wood stoves?

[AMC RULES 37,127]

What is the diameter of the hole you're looking for? 

Got a local tool rental? Might try there first. 

 

https://www.amazon.com/Core-Brick-Concrete-Block-Pilot/dp/B077RC2FTT/ref=asc_df_B077RC2FTT/?tag=hyprod-20&linkCode=df0&hvadid=309869401414&hvpos=1o8&hvnetw=g&hvrand=15120860865290059093&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9004836&hvtargid=pla-582370321416&psc=1&tag=&ref=&adgrpid=63364097444&hvpone=&hvptwo=&hvadid=309869401414&hvpos=1o8&hvnetw=g&hvrand=15120860865290059093&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9004836&hvtargid=pla-582370321416

[wallfish 16,983]

Core drilling is the way to go. Wet core drill with the proper drill and bit is the best but it can be done dry too. Makes a nice clean round hole

You can rent a wet core hand drill and proper size bit. Tile is no problem with a core drill but it's slow. That stuff is hard.

I core drill concrete, brick, block, tile every day so if you have any questions about doing it let me know. 

Edited August 27, 2019 by wallfish

[ebinmaine 67,266]

You folks are awesome. No way around it.

34 minutes ago, Burnerman said:

What are you venting? 2 wood stoves?

Back in February we had a major oil spill in the basement. After that we removed the entire oil heating system from said basement.

We have a 2 flue chimney.

1 is for the large Fisher wood stove in the cellar.

The one that used to be for the oil furnace is now going to be used for the small stove that we are putting upstairs.

 

[Burnerman 758]

Ah. Got it! Wallfish sounds like the best guy to get info from. The only thing I’d recommend is get a SS liner for it from there up. It’ll ensure a tight seal at the new penetration and drilling the hole and compromising the liner are not an issue. Also safe and easier to keep clean. 

[ebinmaine 67,266]

37 minutes ago, wallfish said:

I core drill concrete, brick, block, tile every day so if you have any questions about doing it let me know. 

jeez John it's too bad you're headed south next weekend instead of up here to Maine like you SHOULD be.

I'd much rather throw money at you than someone I don't know.

 

John to Mrs 'fish:

Sorry I can't go to Jersey. Gotta work.

In Maine.

Yepp.

[AMC RULES 37,127]

I bet Trina could do this Eric.   

When she does...we want a video. 

 

[bc.gold 3,403]

I make a paper washer ( album cover ) that I place between the core drill and the drive shaft, it makes removing the core drill so much easier.

 

Also place a paper washer between the wire brush cup that threads onto an angle grinder, this was my first use of paper.

Edited August 28, 2019 by bcgold

[JERSEYHAWG / Glenn 4,497]

Check with the supplier on the stove you intend to vent. You migh be better off side wall vent with the double stainless liner. Heres why. It the existing flue is to  large and the run (Height) is to long, the warm exhaust gases will cool and wont make it to exhaust through the top. Hence they backvent, carbon monoxide. It oderless and can kill you. Just be carefull is all. I have seen this done wrong many times before. 

[ebinmaine 67,266]

6 hours ago, JERSEYHAWG / Glenn said:

Check with the supplier on the stove you intend to vent

Can't do that because it's an older stove that was a gift from a friend of a friend.

 

I did have the local fire chief over to the house to inspect the site and approve what we wanted to do.

 

ALWAYS appreciate a safety reminder.

Thanks Glenn!

 

[ebinmaine 67,266]

7 hours ago, AMC RULES said:

I bet Trina could do this Eric.   

When she does...we want a video. 

 

Craig you KNOW she'd tackle that !!!

 

 

[SylvanLakeWH 25,490]

8 hours ago, JERSEYHAWG / Glenn said:

Check with the supplier on the stove you intend to vent. You migh be better off side wall vent with the double stainless liner. Heres why. It the existing flue is to  large and the run (Height) is to long, the warm exhaust gases will cool and wont make it to exhaust through the top. Hence they backvent, carbon monoxide. It oderless and can kill you. Just be carefull is all. I have seen this done wrong many times before. 

 

 

1 hour ago, ebinmaine said:

Can't do that because it's an older stove that was a gift from a friend of a friend.

 

I did have the local fire chief over to the house to inspect the site and approve what we wanted to do.

 

ALWAYS appreciate a safety reminder.

Thanks Glenn!

 

 

I would chat with a mechanical guy also. They spend their days calculating such things and making sure it has adequate draw...

 

Also, put a co detector nearby...

 

[AMC RULES 37,127]

1 hour ago, ebinmaine said:

Craig you KNOW she'd tackle that !!!

 

 

 

  Well, sure...

who else is gonna do it?  

[stevebo-(Moderator) 8,330]

I have had too many close calls with fires .... pony up and hire a professional. It will save you in the end. Just my 2 cents

[ebinmaine 67,266]

37 minutes ago, stevebo said:

I have had too many close calls with fires .... pony up and hire a professional. It will save you in the end. Just my 2 cents

Yeah we're still exploring the cost factor. It may end up being almost the same amount of money to buy a bit as it is to have somebody come in and do the work for us.

 

IF we do end up doing it ourselves it will be inspected every step of the way by the fire chief.

 

 

 

[ebinmaine 67,266]

1 hour ago, SylvanLakeWH said:

 

 

 

I would chat with a mechanical guy also. They spend their days calculating such things and making sure it has adequate draw...

 

Also, put a co detector nearby...

 

 

 

Appropriate detectors are in place.

 

Good idea on the HVAC person. There is a twin flu in this chimney that has a wood stove on it and does perfectly fine so I should be okay but I will ask.

 

[WHNJ701 4,165]

why did you get rid of the oil heat? 

[ebinmaine 67,266]

4 minutes ago, jabelman said:

why did you get rid of the oil heat? 

Notwithstanding the spill it's something Trina and I had been talking about for a couple years.

The system we had was old inefficient cheap technology when the house was built in 2002 and it was beginning to require repairs.

 

At the time of the spill the tank was dated at 19 years.

if it was 20 years, or older, the DEP would not have let us reuse it.

We've had two different oil heat installation and repair companies come in trying to seal a leak where the tank meets the filter.

We were heading towards a situation of replacing the tank.

 

Keeping in mind that we had already been mulling over getting rid of oil heat anyways we decided that replacing the tank was NOT an option.

 

 

Gas heat was going to be a consideration but the installation cost alone was going to be between $300 and $800 depending on who we talked to. That does NOT count purchasing the system. That is ONLY the labor for installing it.

 

Underground heat exchangers are not an appropriate primary heating system in our area because it gets too cold. They are also a little on the loud side when running and we spend a lot of time in that area.

 

We've already installed a new high-efficiency electric 40 gallon water heater.

Our electricity bill has gone DOWN in comparison to previous years when we were using oil to heat the hot water.

 

This coming heating season we will switch over to electric heat to keep the house between 50° and 60°. Warmer than that, wood stove.

 

[stevasaurus 22,706]

  Can't talk to you now Beaver, I have to go over to Eric's and inspect a hole in his chimney.  

 

[jebbear 377]

Just my  worth, but don't totally rule out the gas option. Not sure what gas costs are in your area, but fortunately we already have gas installed in our area, and the daily operating costs alone are way less than electric. A few years back, I replaced our old furnace with a new high efficiency one with a heat pump, and the savings alone offset initial cost. Turned out to be a great investment.

[ebinmaine 67,266]

47 minutes ago, jebbear said:

gas

I should have specified that a little better.

We don't have piped in natural gas. We live in the middle of nowhere.

 

Ours would be a propane tank installation.

 

HUGE investment when you combine the labor cost and the price of the unit and then have to purchase propane at $3 to $3.50 per gallon.

 

 

[Burnerman 758]

10 minutes ago, ebinmaine said:

I should have specified that a little better.

We don't have piped in natural gas. We live in the middle of nowhere.

 

Ours would be a propane tank installation.

 

HUGE investment when you combine the labor cost and the price of the unit and then have to purchase propane at $3 to $3.50 per gallon.

 

 

Propane is expensive to heat with. I worked 20yrs with Agway energy and 8 with Suburban-propane after  the buyout. I understand what you’re dealing with Eric. 

That said, I have a HE on demand gas water heater that’s been awesome and sips LP. The other nice thing with gas is it’s easy to run during power outages. I have a vent free gas stove in the living room that we use occasionally that needs no electricity. 

if you have electric heat in the house already and reliable electric supply use wood and supplement with wood.