Introducing: Fort Denali

[mkrepel]

Greg,

The house sure looks good. I really like the woodwork around the garage doors. It looks like your carpenter is quite an artisan.

I still have it on my list to stop in and take a look. We had a busy fall...maybe after the holidays.

Merry Christmas,

Mike

[GreginAlaska]

Hi Mike, ya the guy that did the wood is pretty talented, we used ash for that trim. He's also the same guy that cut the ICF forms for the radius curves, built the roof on the garage, built the eaves and the spiral staircase. We ended up leaving the masking on the woodwork too long and it is pretty hard to get off in the cold, we will get the rest off and refinish it next summer, we will also finish the rest of the decorative concrete then. His name is Steve Contois and he owns Long Hair Lofting & Millworks. The guy is fair priced but works at his own pace. Leila said she saw him at Home Depot yesterday and he was headed to Talkeetna with a spiral staircase he had made totally out of cherry wood, she said it was beautiful.

Maybe he will put a pic on his spiral staircase page pretty soon

http://www.longhairloftingandmillworks. ... rcases.php

[GreginAlaska]

Got the heat going in the living area.

[GreginAlaska]

another ///////////

[BWARDEN]

Hi Greg,

What kind of pumps are you using in your heating system? Do they have integral check valves? How are you doing the zone temperature control? Are you controlling by air temperature or slab temperature?

Glad to see you are making good progress.

Bob

[GreginAlaska]

Hi Bob, Thanks

I'm not sure what brand of pumps the plumber put in, I just let him go with what he felt was best. I do know he used a Lochinvar Knight boiler, he said I would be able to switch it from controlling air temp, output fluid temp, return temp and something else...system temp? Right now he has it locked at 20% of the max output, that works out to 31,000 btu, and it is running 4 of the zones and we have glycol for the fluid. I think we will end up with 9 zones and each zone will have it's own thermostat controlling air temp. Would it be better to control slab temp somehow? It's been in the -15 to -20 F lately and the air temp has been 55 - 60F inside. I guess that is not too bad for not having the doors and windows totally winterized and just a tarp covering the top of the tower.

[BWARDEN]

Well, Greg, I'm still messing with controlling my radiant floor. The problem with controlling by air temp is that air temp can change quickly, but radiant floors change very very slowly, so controlling by air temp is not going to be ideal. The return water temp is going to be essentially the slab temperature. I'm wondering if you should control the return temp based on some curve in relation to outdoor temperature. The outdoor temperature determines the required heat load, and the difference between output fluid temp and return fluid temp is how much heat you're putting into the floor. By using outdoor air temp you will know asap when your heat load needs to change and you can begin to ramp up the floor temp a little. A good man could probably calculate the curve required, but it might be as easy to use trial and error. This is what I'm going to do on my floor, but, it hasn't come up to the top of the list yet. Right now, all my solar hot water goes to the floor and I get what I get there. The difference is made up with hot air from the heat pump and my water based air handlers. The heat pump is also connected to the radiant floor, but I don't have the controls for that in place yet. If only I didn't have to sleep.......

[timbau]

Greg did you get buried by the big snow? Was wondering if you were snowed in till spring.

I've always wondered how this in slab heating worked. Heating isn't a real big concern here in TX. We were near 80 the other day. Today is a bit cool. We're suppose to warm again tomorrow. As Bob said I would think the warming of a slab would take some time and you would have to be proactive instead of reactive. I would think that you could use those charts that states produce concerning relative temps for an area. Use them to anticipate based on outside temps. Would be nice to have a automated system to regulate the process. Just my 2 cents.....

Keep us informed of your findings. Always interested in these types of things.....

[GreginAlaska]

Hi Bob, I know the boiler does have the capacity to adjust its firing rate by looking at the outdoor temp. I guess I would have to have sensors put in each return to control the different zones, right now the return temp would just see the combined temps of all zones. I'll run it by the plumber.

Thanks

[GreginAlaska]

Hi Tim, we didn't get the big snows like they did down in Valdez and Cordova, but we are getting a fair amount.

This is the first time I've had in floor radiant heat, but I have heard many people talk about theirs. Most really like it but the one complaint many seem to have is how long it takes to change temps. So proactively is probably better than re actively.

[timbau]

Greg

I thought I would check in & see what you were up too. Also, to see if you've managed to get the kinks out of your heating system. Soon the snow will be flying & winter will be upon us. Hope all is going well & hoping for some more pictures of your progress.

Later

[GreginAlaska]

Hi Tim, I haven't really made a lot of progress on the thing lately, I did get about ~80% of the interior framing done. I had ordered decorative concrete for the tower back in April, it didn't get here until the 27th, I'm hoping we can get that on when I go home for 3 weeks on the 4th.

I had a guy build the tower last year, I was on the slope and he missed one little detail on it...he didn't put in the rebar stub ups for the dome roof, they are supposed to be lap spliced with the vertical rebar in the tower walls, no way to get it fixed exactly as it is supposed to be. I spent some time contemplating what I would do, I though of everything from timber frame domes to copper clad silo domes. I finally contacted the engineer and asked what he would do. He gave me a detail for a MD dome that would be a bit lighter than the original design. I found there is a place down in the states that has a wet shotcrete mix that is 8500 psi @ 28 days and uses all fine aggregates. I was thinking this would be a good thing to bring the strength back to the roof and I could pump it with a little pump I own, it won't pump any aggregate over 1/4 inch. I ordered some of that but just recently found out the plant didn't ship it, so, if I am going to get it done this fall, I'm back to a regular 8 sack mix and renting a real shotcrete set up. That company also claims to make a dry shotcrete mix that is 14,400 psi and uses all fine aggregates.

[timbau]

Hi Tim, I haven't really made a lot of progress on the thing lately, I did get about ~80% of the interior framing done. I had ordered decorative concrete for the tower back in April, it didn't get here until the 27th, I'm hoping we can get that on when I go home for 3 weeks on the 4th.

I had a guy build the tower last year, I was on the slope and he missed one little detail on it...he didn't put in the rebar stub ups for the dome roof, they are supposed to be lap spliced with the vertical rebar in the tower walls, no way to get it fixed exactly as it is supposed to be. I spent some time contemplating what I would do, I though of everything from timber frame domes to copper clad silo domes. I finally contacted the engineer and asked what he would do. He gave me a detail for a MD dome that would be a bit lighter than the original design. I found there is a place down in the states that has a wet shotcrete mix that is 8500 psi @ 28 days and uses all fine aggregates. I was thinking this would be a good thing to bring the strength back to the roof and I could pump it with a little pump I own, it won't pump any aggregate over 1/4 inch. I ordered some of that but just recently found out the plant didn't ship it, so, if I am going to get it done this fall, I'm back to a regular 8 sack mix and renting a real shotcrete set up. That company also claims to make a dry shotcrete mix that is 14,400 psi and uses all fine aggregates.

Greg sounds like you've really been at it. May I make a suggestion?

Remember what you paid for this. I've been doing some research on varied methods of building strong green structures. I came across a group that builds earthships. While I don't suggest it vs a dome they do have some interesting solutions for building issues. On one of their designs uses a fero-cement solution for a domed roof. They form a dome cage out of rebar & chicken wire. Then connect the cage to a bond beam at the top of their walls. Then they take old rags & soak them in a container of low aggregate cement. These cement soaked rags are then applied to the top of the cage. After the cage has been covered, they let it cure for a while. Then you could shoot the rest with shotcrete or put several layer of cement. This would make a real nice top for your tower. It could be sprayed on the inside with foam or what ever.

I'm probably not explaining the process very well & may not be understanding your problem. However, take a look at the following vid & see if that will provide you with some more ideas.

http://www.youtube.com/watch?v=wTqSpx0Vgv4

Simple Survival Model Earthship

Maybe with a bond beam then you could attach the cage & that would fix your problem.

Hope this helps.

[GreginAlaska]

I'll check it out Tim
Thanks!

[timbau]

I'll check it out Tim
Thanks!

Greg no problem.

These guys that build these earthships are masters at building on the cheap. Also, they do some really interesting things with garbage such as bottles & soda cans. You might want to take a look at the earthship vids for other ideas.

Hope it will solve your tower problem.