Raising the Height of the Chimney

I am considering adding a few feet to my chimney next summer for better drafting. Could I please get some testimonials from people that have raised the chimney height and how it impacted draft performance? Please..

I can tell you that adding a 4 foot stainless steel chimney extension from
"X" with a cap and mesh as one peice was a good investment
for my natural draft boiler and the oil boiler.

"I do not want to get in trouble with the administrator for mentioning a brand or the retailer."

The installer drilled holes in the concrete cap and inserted tapcon screws
in the separate mounting base that the chimney extension was bolted into to
hold it in place.

The hand fired boiler perfoms very well when it is cold out as the old chimney
barely cleared the peak of the house.

It all depends on whether you want a clay chimney pot too as they have been used
for many centuries in Europe too.

Lee, you got a block & tile chimney, yes????????? I've never heard of extending the chimney harming anything--at one point, I added 2' to my block chimney in the back w/ the wood beast--I'll just say it didn't do any harm but as far as noticeable improvement--nah--wasn't anything really wrong with my draft to start with. I think I just got bored one day & had the materials laying around:)-what's goin on with your draft?

Lightning wrote:I am considering adding a few feet to my chimney next summer for better drafting. Could I please get some testimonials from people that have raised the chimney height and how it impacted draft performance? Please..

Yes ... I have an exterior block and tile chimney that is only a foot or so higher than the roof peak...

Lee, I can tell you first hand if you can do it go for it. Read the thread I started in 2012 Heed the Warning! the last two pages tell what I did to it, today was 65* the stove was 250*(blower was on slow speed) wanted it lower but thats what it was,pipe at the stove 165*,pipe at the clay 130*,MPD 1/2 closed,OFA was at 1/2, and the baro wasn't covered all while pulling -.045 on the manometer, I think between adding the 2',the round liners,and insulation made a huge difference on my chimney.

Well, I just finished mine today. Only raised it 3 courses - probably 6-8" or so. At 60° earlier today it was pulling maybe .0050" more than it used to. I'll have to keep an eye on it the next few days - got some cold coming, so that'll be a good test. I think the biggest improvement will be on windy days, since it's that much higher than the roof peak than it used to be. If I remember right, it was exactly 3' above the peak. Now maybe 3.5' . I'll measure it tomorrow - have to caulk a tiny section I forgot to re-point, and try to clean up the mortar I slapped all over the bricks & roof. I was in a mortar-slinging frenzy these past 2 days.

Another reason I ask is because it seems that people with interior chimneys have more draft than they know what to do with. So, I'm wondering if insulating an exterior block chimney to keep it warm would have a better impact on draft health and consistency..

Insulating liner in the chimneys is the best.
Wrapping brick/block outer structure not so much...too much mass to bring up and hold temp in.

YES, I would extend the chimney but surely wait & see how that works before worrying about insulating Lee!

Lightning wrote:Yes ... I have an exterior block and tile chimney that is only a foot or so higher than the roof peak...

McGiever wrote:Insulating liner in the chimneys is the best.
Wrapping brick/block outer structure not so much...too much mass to bring up and hold temp in.

freetown fred wrote:YES, I would extend the chimney but surely wait & see how that works before worrying about insulating Lee!

Yeah, I tend to agree with both of you.. I suppose doing both would be that much more effective. I don't have anyway to insulate the liner unfortunately. At least I don't think so..

If you are going to raise the chimney( adding brick and liners) you will have to remove the crown anyways now the next thing is the air space between the brick and the liners, I went from a liner with 13" sq outside to a round 10" OD I had a lot of space for the Perlite to flow so for me that was easy to do but just adding a few feet will help a great deal!! If you can get the insulation down between then do it, I paid around $35 for 4 bags of Perlite.

Perlite is a brand name of the expanded vermiculite product.

http://www.dupreminerals.com/en/vermiculite/introduction