insulation while curing

[y8mne]

Hi guys, just a quick question. I have just finished my dome and covered in 1 inch refractory mortar. i am planning on using ceramic blanket (1 inch) and four inches of vermiculite cement and a weatherproof mortar on top.

I understand that the process of curing is to get the moisture out, but here in the uk it is pretty wet and i think it would be difficult to keep the rain off so the dome would end up getting wet - defeating the curing process.
Also some people seem to say that it is better curing with the insulation layer on so as to keep the heat in the bricks/dome more even. I cant help thinking that it would be better to protect the dome with the blanket, insulating layer and render so as it can all cure evenly. I also expect some cracks in my dome but from what i see on the forum i wouldnt be fixing them anyway and would continue to cover with my insulation. This is the only benefit i can see for not insulating before curing (so you can fix the cracks) but it seems that it may be pointless doing this anyway so curing with all of the insulation finished may be easier?
I have read so many different opinions i just dont know what to believe is the right way!

Marios

[tinaloven]

Re: insulation while curing

G"day there, I too was looking for the "correct way" but have come to the conclusion there a lot of correct ways both with plus and minus on the topic. I have the few that it's better to cure without insulation due to the fact that there is still a lot of moisture which converts to various gases and steam from the mortar used that get trapped and may even dampen and weeken the molecular structure of the insulation. Now by saying that, the insulation is doing it's job, but why burden it with the greatest amount of moisture that it will absorb in the shortest amount of time. For me it makes sence to wait to put insulation after curing. Think of your house insulation in your roof if it gets wet, or enough moisture content within your insulation is not working as effective as it should. Pluse the added benefit to see if any cracks do form with the ability to fix or mend the cracks if you can. More calculations on the steam/gases on the effects of the insulation integrity. Any just my 2cents less tax on the topic. All the best though and I suppose the more we discuss and interact the more we understand. So good question. Ciao for now

[Lburou]

Re: insulation while curing

It seems to me that the purpose of the 'final curing' of your oven can't be final until it is complete to the point that it is weather-proof.

That is why fornobravo recommends a slow and gradual series of curing fires. When you have the oven to a point it will withstand the weather, (read, covered with a permanent waterproof/waterresistant final layer), it is safe to cure it, slowly. Otherwise you are doomed to cure it at least twice.

You surely could cure it before and after the insulating layers. One thing is sure, it will be necessary to purge the oven and insulating layers of moisture before the oven is ready for optimum performance. Just my opinion

[C5dad]

Re: insulation while curing

Don't know about others, but I cured my uninsulated oven, then will do the insulation and cure again followed by the outer scratch coat. My goal is to ensure each layer is cured properly. Seeing that I have a crack to repair, it would have been a PITA to strip the insulation to repair it.

I was surprised by the amount of water that was blowing off the dome during the curing stage! So much so, it darkened my scratch coat - did not help that we had rain the other night as well.

Fortunately, I live in a desert with a huge drying capacity even during the winter - though annual evaporation rate is about 165 inches.

Of course, I could be all wet!

[Neil2]

Re: insulation while curing

"but here in the uk it is pretty wet"

Here on Vancouver Island as well. My last oven was completed through the winter months so I insulated and stuccoed it before curing.

[Lburou]

Re: insulation while curing

Don't know about others, but I cured my uninsulated oven, then will do the insulation and cure again followed by the outer scratch coat. My goal is to ensure each layer is cured properly. Seeing that I have a crack to repair, it would have been a PITA to strip the insulation to repair it.

I was surprised by the amount of water that was blowing off the dome during the curing stage! So much so, it darkened my scratch coat - did not help that we had rain the other night as well.

Fortunately, I live in a desert with a huge drying capacity even during the winter - though annual evaporation rate is about 165 inches.

Of course, I could be all wet!

You are the second poster this week with a smoke leak....I wonder what causes a smoke leak? Its a good think you did things like you did. If I cure before insulation, I will make sure the oven stays dry until the insulation is installed.