Absolutely Cantoo....insulated chimney is always recommended. Theres a couple companies that make stainless steel, double wall insulated smoke pipe. Long Single wall condenses excessively = creosoteBabalugatz, I also have a tall chimney but mine only has about the 1st 6" not insulated the rest is insulated pipe. I have never cleaned my pipe and have never had an issue with creosote, it actually seems to cut down on sparks coming out the top. I still have sparks but not as many.
I don't think I will have an issue. My soil is pretty much all gravel. My house is actually with 100ft from an old gravel pit. Even if the pad heaves, I have a few inches of extra line under the boiler. Nothing was installed tight. However I will keep an eye on it now.breymeyerfam, are you expecting any issue with your concrete pad lifting from frost? It looks like I did pretty the same as you did when I poured my pad. I have a backhoe so I installed my own lines. I dug down 7' for my insulated lines and left them sticking up at the back. I then back filled everything with pit run and A gravel. I then dug down about 8" for the owb pad and room to stand out front. I used 2x6 for concrete forms and the concrete is about 5" thick. When I did it the concrete was about 2 or 3" above the surrounding gravel. It's been about 4 years now and the pad has lifted up approx. 4 or 5". I wish now that I would have put styro foam down under and round the pad. It hasn't caused any issues yet with the insulated lines but I'm starting to wonder if I will have a issue soon if I have more lifting. I really don't want to but am wondering if I should just do some preventative maintenance and move the owb, remove the concrete, dig down again and install the Styrofoam and then pour new concrete? I want a little bigger area anyway. I never cheaped out on anything on my owb, well I thought I didn't but maybe I did in this part. You guys have warmer temps than we do but frost is still an issue there I assume?