Insulating a Leader 2'x4'

[Green Hollow Maple]

Just wondering if anyone has used arch board prior to bricking their Leader 2'x4'? If so, how many square-feet of arch board were needed to adequately accomplish this?

[JohnsSugarShack]

I would definitely use arch board, I think it makes a big difference. I insulated a Leader 2x6 raised flue and only had a couple of scraps left over from 16 1'x3' pieces that I bought from Bascoms. I covered every square inch of the arch even under the grates. I would guess that you would be fine with 11-12 sheets.

[3rdgen.maple]

Why not just measure the surface area inside your arch and then order an extra peice?

[Haynes Forest Products]

You need to go by sq ft but also how many sheets will do certain areas so you dont have alot of tiny peices falling out. Its like tile work sq ft will give you the price of the tile but then when it comes to lay out you need to find the size that fits the job.

[Green Hollow Maple]

When I buy and take delivery of the arch I will gladly measure the inside surface area. I was simply trying to put some rough budget figures together prior to Bascom's open house where I plan to purchase everything I need (arch included), while taking advantage of the 10% discount. Thank you for the constructive feedback.

[sugar man]

when i built my 2x4 i used 1/2 blanket i got off ebay.i put two layers down and did the door made a big diffirance now you can stand next to the evap when going full bor.:)

[C.Wilcox]

I have a homemade 2X4, but for what it's worth, I think I used about 7-8 of the 1X3 sheets of archboard.

[steve J]

When you use this arch board do you also insulate the bottom of the evaporator prior to putting down the bricks? I assume that if we are keeping more heat inside the evaporator then the boil rate should be higher correct?

[C.Wilcox]

By "bottom" do you mean the bottom of the firebox? If that's what you're asking I would say no. Most evaporators have grates as the bottom of the firebox and you wouldn't be able to use archboard with them. When I pull the ash pan out of my evaporator I can just about hold my hand under the grates despite the fire going full bore. Not much heat loss down there. Theoretically anything you do to prevent heat loss should help your boil rate, but I think there's a practical limit to it. You just can't transfer all of the heat from the fire to your pans unless you have flues or a really long flat pan. The heat doesn't have the residence time it needs to be absorbed into the pan. So if you overinsulate your arch and are using a short pan all you'll do is send the extra heat up the chimney. That's fine if your goal is to keep the temperature of the arch itself down to help avoid potential burns while cooking, but I don't think you really gain much more in the way of evaporation efficiency.