Rocket mass heater review after two years of use. The truth about mass heaters! 

Super interesting points about how the damper functions for you in a high-wind environment, I wouldn't have thought about the gases being pulled through the bench too quickly. Thank you!

this is great to hear. there are so many who've built a rmh and put up reviews when first built, but rare to see the long term reviews. just need you to pop down to Stockport and give me a hand building mine! stay toasty. oh, cover for the burn chamber - look for a small anti splatter cover for a frying pan

Speaking of being good with heat, on of our previous cats learned to flick the kettle on so she could keep herself warm overnight. I always refill for the next person but my mum doesn't so we had 2 kettles burn themselves up because of that

Very inspirational! I've been looking for a series of videos to get me started on a RMH for our home. Your series was just the ticket. Thanks for an interesting, inspirational and entertaining video.

I was so glad when I found your channel a few months ago …. to find folks who think like me! Wanted to also let you know that Paul Wheaton spoke favourably about you in his livestream last night. Thanks for sharing your wisdom and knowledge - much appreciated.

I've long been fascinated by different methods of burning fuel wood. The advancements in wood burning in the last 30 years or so have been incredible, both in the exploitation of "rocket" designs that burn fast, hot and clean, but also in traditional wood stoves, that now gracefully and steadily perform most of the combustion of the wood "above" the wood in form of secondary combustion and catalytic combustion, which, combined, allow for fairly extended burn cycles and subsequent heat life from some of the heavier stoves. We do about 75% of our heating with a relatively large modern wood stove mostly just because I enjoy processing wood and making fires. I estimate we burn on average about 2 cubic foot of ponderosa per day through the "heating season." That's around 330K BTU per day "burned" and I estimate about 250K BTU's stay in the house. The remaining BTU's are used to safely discharge the non-condensed wood gases out of the wood heating system so that the chimney and stove pipe stay pretty clean and safe over time. Since we burn very sooty pine here I clean the chimney, stove pipe, and cats out 2-3 times per season. The system frequently produces that ideal "just steam" exhaust that condenses into the cold air as a white cloud inches away from the chimney cap. I call that a win for balancing efficiency with ease of daily use and maintenance considerations. I see a lot of these video's on rocket stoves but often feel they are presented without a clear picture of how much fuel is being burned daily when one of these is used as a primary heat source. I would expect these these can produce 95% or better efficiency much like a modern condensing natural gas furnace, but at what cost in terms of cleanout? I sometimes wonder if the reason these appear to produce such clean looking exhaust is that a lot of the particulates are being left behind in the system and "drained down" with the condensate. You mentioned having some issues with green wood, but even dry wood produces a significant amount of water vapor in the combustion process. I wonder how the "long term" on these works out with regards to deposits in the system. I love how your design has lots of cleanouts! Very wise!!!

Good to see you both in the video!

Thanks. Stay warm and toasty!

Wonderful review!! Thank you for taking the time to do this.

So delighted you gave a review after you have lived with it!

great review. i didnt realise that you're in caithness. i'm renovating an old place near Halkirk and planting willow and planning on putting a couple of rocket mass heaters in the house too as i want a rocket mass bed in my bedroom and then a rocket mass sofa in the living room as my house is very long. I was thinking exactly the same regarding the baffle in the chimney pipe because the wind howls where i am, as i can see the flow country on a clear day and see orkney the other direction and the wind just rips through here at the top of the river thurso valley. Storm babet last week gave me 63mph gusts for about 48 hours. When i rebuild my big outbuilding and add an upstairs floor i'm planning on more rocket mass heaters and specifically one which is a staircase but i'll need to look if that's possible. If it isnt with the rocket mass, then i have seen staircases made with masonry heaters, so i'll just build one of those as then it serves 2 purposes - heating and stairs which is perfect. until the willow grows, ive got loads of wood offcuts as i have a sawmill as i buy logs and cut my own wood to do the renovations on the house. Currently i'm in a static caravan with LPG central heating and its killing me as theyve put my LPG up by 62%, I'm hoping to get roofed next summer and may even get just one roof done over winter to have a dry work space as i got nothing done this summer due to all the rain stopping me using power tools outside all the time and stoppingand starting and taking tools out then in then out and in until you just give up for the day.

15C? The only scenario where that would not be uncomfortable is if you have a super-warm summer and desperately want to cool down... Sweating in 24C on the other hand? I don't it's allowed to DIY a rocket mass heater (or self-made fireplace) in my country - would need to hire a professional I believe. First winter in our new (old) house coming up now - we do have a modern oven in our living room though (but the very first generation of them) so will be interesting to see how we fare (in the bedroom we have an old oven - that one doesn't seem to be very efficient...)

Love it.

Fabulous!

Thanks for the review of your rocket mas heater. That is bizarre that a crow went down your chimney!

Very good to hear what you have learned , thank you for your video.

This is brilliant. I am intrigued, instead of a bench could the flue pipe system be used under a floor?

Damper? I live in South Dakota, might as well be the channel all the wind gets to America through from Canada. A flue damper 19:05 is definitely necessary.

Thanks for these videos. I am putting together a RMH project and I have a question. You have the bench made with cob and stones. What element heats up faster, the stones or the cob. Conversely, which cools down first...are the stones still warm after the cob has cooled?

Great review I myself made a thermal mass roket heater and we love it ! I'd like to know what you think of it if you would take a look ? My only regret with ours is we don't have the availability where our fire is to put a cob bench so it's only the roket and sand battery that we use but it does an amazing job . We are also in a town so no chance for us so be sustainable with out own branches however I have a plan for that with asking for branches from local tree surgeons that way they don't have to chip as much ! Hmm cunning plan I have right ? Nice to see a UK stove too no offence made there 😅

trust snoop to show you a potential fire risk, with that tail down the burn chamber, lol! cats! i also like that idea for a cook's spattershield what's your average winter temp now, comparing to that bracing 15°C pre install? informative and inspirational, thank you🙏👍

Is the ash that's created a bio charr byproduct 🤔. Where does the bio charr come from. Thanks for making this video 🤗

Very good video, thanks for sharing! Any reason you did not go for the stratification mass heater so no pipe rather than the pipe version? Thanks.

I remember watching your original rmh video when it first came out so great to hear its still going strong! One question - where you mentioned newer models use a stratification chamber. Im assuming this is the "bell method"? If so do you think theyre as good (or better) than the pipe method you've used?

Any thoughts on cob/haybail retrofitting the exterior of the old building? Excellent stuff anyways friend's

Would you still go with this design if you could redo it or would you go with a batch heater, also would you incorporate a design which gets hot water from the mass heater too

Great job. What size is your house? My house is 450 square meters. Would it work in my house?

Aren't you the one who had to redo the floor supports, fill in the fireplace that had a heating tube for water? I literally watched that video last night.

So if I want electricity to still be working in 4 centuries (not really something one should want, but...), I should invest in building a 30 brake horsepower steam engine with a rocket boiler, and building a self-exciting dynamo?

Here's the problem I had with my homemade refractory out of regular morter, and perlite : ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-wFLrhgPxoXk.htmlsi=Q8iPbisH-4vbMHEN

So how much wood do you end up using a season? One, two, three cords?

Hi mate weherr are ye from, Alba? Sorry Scotland? Cairn of Dunn, sounds as a place in Scotland I been in dunfermline, not to far the north crossing the firth of forth, Fife

Bu where is this legal, ul all that jazz. They would kick me out of town, bank would no loan, insurance would cancel