Thermal mass across whole floor or biased centrally ?

[uk_exile]

Re: Thermal mass across whole floor or biased centrally ?

Oh, that's quite different than I thought. I may need to recost it all as will be able to get recycled red house bricks. Probably still more expensive than new house brick but will be less than new or used fire bricks. Factor may become increased insulation needs & higher wood cost vs the insulated brick less insulation design.

[Laku]

Re: Thermal mass across whole floor or biased centrally ?

Roman ovens were made of "normal" red clay bricks. They are still around.

[Tscarborough]

Re: Thermal mass across whole floor or biased centrally ?

Insulating refractory is used in situations where you want to store a liquid or gaseous material with minimal energy input, i.e. a kiln or a boiler. Firebrick are used to store heat, i.e. an oven.

[uk_exile]

Re: Thermal mass across whole floor or biased centrally ?

So old red house brick will be ok but they just won't store as much heat as true fire bricks. Correct ?
Seems most builders on FB use fire bricks. Is that a bit over the top for a 4 person family domestic use ? i.e. has excess storage

[Tscarborough]

Re: Thermal mass across whole floor or biased centrally ?

Basically, the old method of making bricks is the same as the modern way of making fire bricks, but not modern brick. That is, they are drypack pressed not wet extruded like modern brick. They will hold about the same amount of heat, but the firebrick ARE more durable, and have slightly better physical characteristics (very accurate sizing).

In some parts of the world, old common solids are not very common, or if available they are almost as expensive as FB and pretty beat up. In this area, we also have a brick industry that makes brick by hand, wetpack in wood molds and fires them at relatively low temperature. These will work for an oven as well, but they erode quickly, so even though they are dirt cheap, I do not recommend them.

[Tank]

Re: Thermal mass across whole floor or biased centrally ?

if the bricks weren't $6 each making the build 3x the cost what these alternative designs

I have often thought it would be worth importing 1/2 a container of them to sell down here. You could make some $$$$ undercutting place makers etc.

[uk_exile]

Re: Thermal mass across whole floor or biased centrally ?

Certainly arranging a group buy & importing a few ovens worth of firebricks from USA would save heaps of $$$$ for a group of WFO constructors. Not so sure just importing a lot then trying to sell would work as suspect most kiwis keen on a pizza oven will just buy the steel box glorified hood BBQs, or will stump up $3k - $7k for premade.

[Gulf]

Re: Thermal mass across whole floor or biased centrally ?

May want to include those who want to build a fireplace. I understand that it gets cold in yall's "summer" .

[uk_exile]

Re: Thermal mass across whole floor or biased centrally ?

May want to include those who want to build a fireplace. I understand that it gets cold in yall's "summer" .

Being a relatively small island in a large ocean certainly causes our summer to vary day to day. Been plenty of 22 - 30 degC days recently. A cold day could be 15 degC. Evenings can be cool.

Installing or using outdoor fireplaces will become more difficult as many councils are bringing in 'clean air' regulations. Basically they allow only certain high efficiency fully enclosed burners for house heating & certainly do not allow old style open fires. The work around for WFOs is all include a rule allowing fires for 'food preparation' hence simple BBQ, pizza ovens and oven a simple drum with grill over top is acceptable.

[Gulf]

Re: Thermal mass across whole floor or biased centrally ?

Installing or using outdoor fireplaces will become more difficult as many councils are bringing in 'clean air' regulations. Basically they allow only certain high efficiency fully enclosed burners for house heating & certainly do not allow old style open fires. The work around for WFOs is all include a rule allowing fires for 'food preparation' hence simple BBQ, pizza ovens and oven a simple drum with grill over top is acceptable.

I was thinking about indoor fireplaces. They are very common where I live. Many people have gone to the insert for their fireplaces. Not because of regulations, just because they heat better with less fuel. Mine is just the "old style fireplace". For many years, in our cold wet winters, I would cook in it. I used a "tuscan grill" over the hardwood coals. I did not know what it was called then . I wonder if that would be a way around the regulations handed down by the "Greenies" who want to live for ever? .

[uk_exile]

Re: Thermal mass across whole floor or biased centrally ?

Wouldn't most indoor fireplaces be built with insulating firebricks, not heat retaining ?

Christchurch were I live has had a clean air policy for many years. It's because of landscape the fire pollutants tended to settle in a natural thermocline, trapping them & causing issues for some children, elderly, asmatics, etc. Inserts became common about 30yrs ago & about 15yrs retro fits or new installations would have had to be an approved efficient clean type that means certain emmission rules. Use of traditonal open fires was completely banned a few years ago. A couple of years ago no new fires were allowed, even with approved inserts & recently use of non approved inserts was also banned. Within next 10-20yrs will probably be zero solid fuel burners in use.
The large earthquakes we expereinced in last 2yrs have knocked down the many old chimneys (& houses, new & old) so it has naturally accelerated the process. No new houses are allowed burners of any form.
I consider it a good thing (if the electricity supply can support it) as the air & views are definitely much clearer now than they were a few years ago. Occassional fire use the enviroment can cope with but full time primary household heating use it simply can't. Also we don't have vast area of firewood trees so fuel is not super abundant anymore.

[Gulf]

Re: Thermal mass across whole floor or biased centrally ?

I understand a little more now about your area. We have a little more cold and wet weather than you. I also live in the "country" where houses are not very close together. Hardwood trees are abundant. I am sure glad that we haven't had an eartquake in the Mississippi Valley in my lifetime .

[uk_exile]

Re: Thermal mass across whole floor or biased centrally ?

Didn't expect I'd feel a significant EQ either but there were unknown fault lines right under the city that caused highest vertical accelerations recorded anywhere in world (peaked at 2.5G !!) and are now considered a 1 in 2500yr event. Modern building codes only designed for 1 in 500 or 750 year events so many sturcutres, even modern ones where broken beyond econmic repair. Result was 180+ people dead, over 10000 aftershocks, 6000+ houses needed knocked down (some old, some only a few months old), majority of CBD gone, displaced businesses, ete. Not good. Feels strange that I used to work in 20 storey 15yr old modern high rise office building with 1500 others, it's now completely gone & I now work in a two storey box box with just 50 people.

However we now have a stronger community & in a decade or so will have a modern well integrated & well designed central city. Looking forward to how it will be !

[UtahBeehiver]

Re: Thermal mass across whole floor or biased centrally ?

UK,

"Bookemdanno" did a nice build in the UK using solid reds. Take a look at his thread.

[brickie in oz]

Re: Thermal mass across whole floor or biased centrally ?

is all include a rule allowing fires for 'food preparation' hence simple BBQ, pizza ovens and oven a simple drum with grill over top is acceptable.

Pit a spit in your outdoor fireplace and tell them to go jump..

I cant see a small population like what is in NZ killing the planet with pollution.....