How to Build our Brick Oven Kit | 11. Rendering the Dome

[@FoxxyZella]

Hey Ben, I forgot to say, Love the cooking video!!!!!!!!!!!

[@TheFireBrickCo]

Awesome! Thank you!

[@FoxxyZella]

Hey Ben, I love your videos your knowledge is impressive. Can you use high heat mortar with perlite for the rendering of the dome? Thank you for your help and your videos!

[@TheFireBrickCo]

Thankyou! Hmm it depends on what you mean by 'high heat mortar' - there are a lot of different types out there and most of them wouldn't be suitable. If you have insulated the dome properly with ceramic fibre blanket then you can just use a blend of ordinary Portland Cement, Hydrated Lime and Washed sand as we do in the video. If you're asking about making the internal dome with Perlite - that's not something that I could recommend.

[@FoxxyZella]

@@TheFireBrickCo Ben, Thank you so very much for your time and reply. I will do as you say again thank you! You are awesome!!!!!!!!!!!! I will keep watching you videos Thanks John

[@robertjames-life4768]

@@TheFireBrickCo hi, why don’t you recommend making the internal dome with a perlite render?

[@sureshmahatheva1732]

hi very helpfull video. as im building tandoor at the moment, im think to render the same way as you doing. great work. you are using perlite. can i use vermiculite and perlite together. because i have them mixed. thank you

[@TheFireBrickCo]

Hi Suresh, I would recomend using Treated Perlite - designed for use in making lightweight concrete as opposed to use in hydropnoics (the latter will make a very weak render mix)

[@olelarsen9089]

A well directed video...thanks for taking the care!! Will the render also act as a water proofing from the rain and weather too? Hope you wont read this now and are enjoying your xmas break :-)

[@TheFireBrickCo]

Hi Ole, there is another coating that goes over the dome to keep rain out, however this is only suitable if you live in a relatively warm climate. If you get snow and freezing conditions in your area then you would need to build a shelter over the oven to keep it completely dry.

[@stuartjones7903]

Hi Ben excellent video , I texted last year asking if you are supplying to UK and to advise using heat resistant rope belween the dome edges not sure if you are now using that .Another question now is that have you ever heard of using foil over the insulating blanket before you apply the render ,I heard it prevents the insulating blanket absorbing the moisture from the render , is this true

[@TheFireBrickCo]

Good questions Stuart! We haven't started doing that just yet because I'm a little concerned about coating over the ceramic fibre rope with the membrane coating that we use. But I'm open to ideas! I've heard of foil being used but my concern is longevity - the combination of reasonably high temperatures, steam and some alkalinity from the mortar in the dome will likely attack this layer and make it decompose fairly quickly, which would then 'render' it pointless. I'm experimenting with grade 309 Stainless steel foil right now for a layer to protect the Calcium Silicate board and it's going really well

[@travcom]

Any chance that an ecommerce site exists that extra Floats could be purchased for delivery to the US? Or even to be shipped from Down Under...... cant cost too much to ship a few pieces of foam?

[@TheFireBrickCo]

There is indeed such a site - might be a bit expensive for shipping to the USA but you can definitely check it out! melbournefirebricks.shop/

[@basilloizou1942]

Great video what size is the chimney?

[@TheFireBrickCo]

It's a 7" stainless steel flue

[@frankinhiro]

Is the perlite mixed with regular cement or refractory cement? Thank you!

[@TheFireBrickCo]

Because the perlite is on the outside of the ceramic fibre blanket, it's mixed with normal Portland Cement, as the temperature on the outside of the blanket is well within what Portland Cement can withstand.

[@frankinhiro]

Thank you! I'm in Japan and making a pizza oven now. I'm using your videos as a Bible each step of the way. What is the ratio you use for the perlite and cement? 6:1?

[@MsCs2009]

Hi. Can the perlite render be extended over the top and sides of the brick arch and over the flue gallery to insulate them? In another video you mention that the flue gallery gets very hot which concerns me a bit. I'm also thinking this would then allow me to extend the dome finish (render, tiles, pebbles etc) over those parts as well as I'm wanting a more "rustic" looking finish and not sure about the black paint would fit the style of my place. Thanks.

[@TheFireBrickCo]

Good question! We haven't done that in the past, mainly because you would probably get a lot of cracking in that perlite, as the front of the oven expands and contracts on heating and cooling. I think you would also find it hard to get the perlite to bond well to the bricks and flue gallery in the long term.

[@rajanshrestha6498]

can we use regular ciment for perlite rendering ? plz do suggest. Thank you.

[@TheFireBrickCo]

That's what we recommend - the ceramic fibre blanket protects the render from extreme heat so you can use regular Portland cement in your render shell

[@nick50]

Where do you get fine perlite

[@TheFireBrickCo]

Do a Google search for it in your area - look for Perlite that's designed for building materials rather than garden use.

[@beniceffs]

Great videos Ben. Just one question, what do you add to the perlite render to water proof it?

[@TheFireBrickCo]

Good question! Nothing - we waterproof it later, once the oven is fully cured, using a flexible membrane coating.

[@JoshHenery]

I've seen other people on youtube use a perlite render and it looks rough, how do you get a smooth render? Is it a finer grade perlite?

[@TheFireBrickCo]

Good question Josh - it's called Litefill 'Fine Perlite', I think the key is that this type of Perlite is actually treated in a solution to make it water-resistant, whereas normal Perlite is designed for use in hydroponics, and actually holds water. As a result, our mix is much easier to apply

[@Freedom94384]

Thanks for sharing your knowledge man I have one question :What’s the ratio in the Pelite mix ?

[@sanman8530]

can we do away with perlite and just use the regular cement ?

[@TheFireBrickCo]

Great question! The Perlite is mixed with GP cement to create a 'high-build render' with great insulating properties. Without the Perlite, you have a very dense render which would require a LOT of cement, to build up a thick shell. It wouldn't be as good as an insulation layer, and would likely cost more. So no, it's not something we would recommend.

[@sanman8530]

@@TheFireBrickCo when I said regular cement I meant Portland not the refractory cement. I hope Your response was for the Portland mix. I've no issues with using Portland as I've that in plenty and what I dont have is Perlite. You said dense render wouldn't be good as an insulation layer. I've already added a 2 inches layer of mineral wool and covered that with Portland mixed with sand and lime. My final cladding was portland mixed with water and sand. would that do or have i ruined it with the final layer ?

[@philkalowski6831]

Where can I buy lite fill perlite in the states ? can’t find anything other than the kind used in gardening thx

[@TheFireBrickCo]

Hi Phil, I'm not sure sorry - perhaps look for perlite manufacturers in your region?

[@Jim-K-Baker]

If I'm putting it on in layers, how much should I mix at a time?

[@TheFireBrickCo]

Hi Jim, I typically mix as much as I can in one go - so use the biggest tub you have, or half-fill a wheelbarrow. Aim for somewhere around 50L, but if you mix less, you can always make another mix... If you mix too much, you've wasted it.

[@abdullahalbuzilfah615]

Hahahhaaa , get some new friends 🤣😂

[@TheFireBrickCo]

Hahahahaha

[@hankburton2043]

And with a beautiful oven like that it won’t be hard to find them lol nice work mate