Questions on Pellet Boiler for New Home Build

[Briarwood]

Hello, I just stumbled onto this forum last night and have been reading ever since. What a fantastic resource of information.

My wife and I have a 2 acre piece of land in the Matunuck section of South Kingstown, RI that we have cleared and are building a home on. We have just hired an architect.

The land does not have access to town water or natural gas and because of its proximity to the ocean it needs an Advantec septic system.

We would love to stay away from oil or propane except the using propane for the cooktop. We debated Geothermal and it's still an option but the up front costs are very high.

I just found the pellet boiler option this morning when researching fireplace inserts. I had no idea they existed as they are nearly non-existant in Rhode Island.

I have liked what I've read so for but have a few concerns.

Do they need a backup system? Is it truly feasible to all my heating and DHW needs? Is the initial cost prohibitive when compared to oil or propane systems?

Thank you for any and all advice. It is truly appreciated.

 

[DZL_Damon]

When I build new, I will do a pellet boiler again for sure. If I do oil back up I'll buy some used $500 unit on craigslist that people are dumping left and right for modulating propane in my area hoping NG will be around soon... it won't at least in my neck of the woods. Why buy a new unit that hopefully never runs?

However, I have not burned a drop of oil since April. Hopefully I can say that in 10 years as well.

 

[velvetfoot]

There are a lot of late model oil boilers on Craigslist here too with the natural gas expansion, which, for me as well, will do no good.

 

[maple1]

I would not install oil if it will only be used for a backup system. I would either go electric (electric boiler), or propane if you will be using propane for something else anyway.

 

[Fred61]

Hopefully the architect you hired is up to date on building energy efficient structures. That's the most important starting point. I don't think you specified whether you had pellets or cordwood in mind for biomass heating. With an extremely energy efficient home some of these systems will take several years to pay back the investment.

 

[maple1]

Not being familair with the RI climate, or knowing anything about what you're building - would mini-splits be an option? New construction offers so much potentail to not need much to heat with.

 

[Briarwood]

Thanks everyone for the replies.

We will be using propane for the cooktop and will be buying and burying a propane tank, haven't decided on a size yet.

If we went with a biomass boiler it would be a pellet boiler. The Biowin series highlighted by a few installation threads on this board look promising.

Does a pellet boiler system absolutely have to have a backup system? If so why do geothermal systems and biomass systems need backup but oil/ng/propane systems don't?

Pellet boilers are very very rare around here. Everyone I've talked to had no experience with the boilers. They are familiar with pellet stoves but not the boilers.

It's surprising because the systems seem to offer many benefits and relatively few negatives.

 

[BoilerMan]

Welcome to Hearth!

Personally I would not install any type of solid fuelled system with out some type of backup. A pellet boiler, no matter how well built will eventually need some type of repair and parts will not be available for a few days. Electric heat is the least expensive backup up front but likely the most expensive to operate.........remember it's backup. If you are going to bury an LP tank, get an inexpensive condensing LP boiler and all you'll need is PVC venting.

I would not use any pellet or wood heater for your hot water in the summer, a heat pump water heater is the way to go for summer water heating. An add-on HPWH can be easily incorporated with a large (80+) gallon indirect, which would be heated with pellets in the winter. You essentially have two water heating systems that share one large tank.

Fred's talk of energy efficiency should be TOP priority. I built my own home myself in 2009 and did the energy homework and we'll just say it really PAYS! My family and I enjoy a warm house in the winter and a cool one in the summer with very minimal heating and no A/C, just the heat pump water heater.

There are many helpful folks on here that can help.

TS

 

[Fred61]

With what I've learned about constructing an energy efficient home in the last 20 years, the smallest pellet or cordwood boiler available would be overkill and would not be needed in any home I built today.

 

[Briarwood]

I know that building an efficient and tight home is incredibly important and it has been stressed to our architect.

Fred, do you have any tips or tricks or hints. If you could share any of your knowledge I would greatly appreciate it.

 

[chken]

Hello, I just stumbled onto this forum last night and have been reading ever since. What a fantastic resource of information.

My wife and I have a 2 acre piece of land in the Matunuck section of South Kingstown, RI that we have cleared and are building a home on. We have just hired an architect.

The land does not have access to town water or natural gas and because of its proximity to the ocean it needs an Advantec septic system.

We would love to stay away from oil or propane except the using propane for the cooktop. We debated Geothermal and it's still an option but the up front costs are very high.

I just found the pellet boiler option this morning when researching fireplace inserts. I had no idea they existed as they are nearly non-existant in Rhode Island.

I have liked what I've read so for but have a few concerns.

Do they need a backup system? Is it truly feasible to all my heating and DHW needs? Is the initial cost prohibitive when compared to oil or propane systems?

Thank you for any and all advice. It is truly appreciated.

First, build yourself a tight energy efficient home. If it were me, I'd build a timber frame with 8-10" SIP walls, and 12"+ SIP roof. If you have a basement, use ICFs. If you can, put 4-6" foam under slab. Of course, you could build to the passivhaus standard and increase all those amounts! Use triple-glazed windows. I have Loewen from Manitoba. Doug fir on the inside, aluminum on the out. Very low U-ratings, which are R-factors for windows. Low is good. SIPs and ICFs are good because they are easy to seal up tight.

If you're financing, ask your bank and insurance company whether any non-traditional heating system is acceptable, like pellet boilers.

If you insulate to the passivhaus standard, you might be able to heat your whole house with one electric radiant baseboard.

If you insulate your house to something less than passivhaus standard, like I listed above, you could very easily heat and cool your house with mini-split heat pumps, and use a hot water heat pump for DHW, like the GE Geospring.

If you are building more traditional, stick frame, fiberglass batt insulation, then I'd consider a pellet boiler like a Biowin or Kedel, or other similar.

If you need an architect who's on the cutting edge of super insulated homes, then I can recommend one near me: http://www.gologic.us/ Their designs have been on the cover of Dwell magazine. The great thing is that they not only design to the highest insulation values, but also may be the least expensive for that level of insulation. They have some pre-designed homes that are $150-$160sqft. I also recommend Kaplan/Thompson architects in Portland, Maine. They're also nationally known for their great, high-insulation designs.

 

[Boil&Toil]

U-values are simply 1/R-value. R-values are 1/U-value. "Resistance" .vs. "Conductance"

Having built one SIP building, (no frame, just SIPs - they are Structural) I insulated the roof with cellulose in a high-heel truss rather than pay for and have to support roof panels.

At present, having been through both ways (and vermiculite), I would not insulate with fiberglass - cellulose does a better job, I think. Building two I'm torn between SIPs again or a twin studwall (offset studs or Larsen trusses) with a boatload of cellulose in it. The R-value per inch is not much different.

Do the energy math sooner rather than later. Make design choices knowing what they will cost you in A: heating dollars B: capital expense for a heating system you might not need if you design the building right. Rather than a boiler, you might be shopping for a hot water heater, essentially. I think Marc Caluwe makes some in stickwood (parlor boilers, if you will - look nice and heat your water), I don't know that there's a good pellet option in the "waterheater" class.

Well kiss mah grits. He's making a pellet parlor boiler now.
http://www.hydro-to-heat-convertor.com/DecorativePelletBoilers.html

 

[jebatty]

Regardless of what you build, design and build for passive solar and keep the roof lines simple; also design for active solar electric and/or hot water on the roof, and if snow is a problem, then active solar ground mount.

Our 1956 house was built inadvertently excellent for passive solar, and even on -20F days in winter we need little to no heat on sunny winter days, yet due to 4' eaves we get virtually no solar heating in the summer. Best of both worlds. Plus the 6.5kw ground mount solar electric we added last fall now has eliminated our electric bill for the rest of time.

 

[Fred61]

I agree with most everything stated above and agree that fiberglass insulation should be avoided if possible. SIPs would be my choice but they may not be for everyone and I do agree with ICFs for the foundation. If you're stick building be sure your architect doesn't get trapped by failing to design in high heel trusses or any other spot that will allow weak points in the insulated envelope.

I would just like to add that an energy efficient home starts down below the footings. The concrete should be high and dry. There should be well draining material below the footings and adequate conduits to take away any moisture. An extra three or four dump truck loads of very porous material when backfilling will pay for themselves over and over through the years. If the soil on your lot happens to be porous gravel, you're way ahead of the game. If it is wicking soil, do your best to keep it away from the foundation. This is an area where supervision on your part is a must throughout the whole process.

 

[sinnian]

I would have some sort of back up heat, and seems like propane would be the way to go.

I would also not recommend using the pellet boiler for your DHW during the non-heating months. I would get a hybrid-electric HW heater, that is plumbed so that when you are heating with pellets the water going into the tank is already hot. In the non-heating months, just close a valve off to the pellet boiler, and open one for the cold water inlet.

Also, yes you do want a nice tight house, put there needs to be air for combustion with any solid fuel/oil/propane heating appliance ~ especially with solid fuels ~ so factor that in on the entire plan.

 

[DBNH22]

Theoretically any heating solution can fail leaving you with a cold home. So I think it's advisable to at least explore the different options for backup heating. As others have said about DHW in the non heating months, you probably don't want your pellet/wood boiler doing that. I have a pellet boiler that does my DHW during the winter but I'm looking into a heat pump water heater solution for the rest of the year. I still have the original oil boiler in place but would like to use it as little as possible in the coming years. That will be my backup for both heat and DHW.

 

[moey]

Our geo system was about 20k. In a new house it would have been even cheaper smaller system less digging. Your looking at more then that for a conventional system and a pellet boiler on top of that. I suggest getting quotes before you rule it out.

 

[chken]

Regardless of what you build, design and build for passive solar and keep the roof lines simple; also design for active solar electric and/or hot water on the roof, and if snow is a problem, then active solar ground mount.

Our 1956 house was built inadvertently excellent for passive solar, and even on -20F days in winter we need little to no heat on sunny winter days, yet due to 4' eaves we get virtually no solar heating in the summer. Best of both worlds. Plus the 6.5kw ground mount solar electric we added last fall now has eliminated our electric bill for the rest of time.

Nice, a mid-century modern!

 

[chken]

Since Fred mentioned footings, I used Certainteed form-a-drain which is a form and a drain, duh! You don't remove them after pouring your footings. They're great because you can use the drain as a radon mitigation system, if it turns out you have radon. Instead of spending $2000+ after the fact, you can spend about $200 by planning ahead.

 

[BoilerMan]

I'm still convinced that a basement is either the biggest waste of heat if done with plain forms and concrete, or very expensive is done with ICF. I'm a slab man, no water/radon/humidity issues. And I'll never buy a sump-pump as about every home around here has!

The storage would be nice, but not worth the expense IMHO.

TS

 

[chken]

I'm still convinced that a basement is either the biggest waste of heat if done with plain forms and concrete, or very expensive is done with ICF. I'm a slab man, no water/radon/humidity issues. And I'll never buy a sump-pump as about every home around here has!

The storage would be nice, but not worth the expense IMHO.
TS

I'll take your word for it, as I only know my one homebuilding experience, but my ICF basement wasn't all that expensive. When I comparison shopped it, everyone told me it would be about 20% more than comparable concrete basements. However, I put in the footing forms (1 day) and built the ICF walls myself (3 days), and it turned out 20% less than a comparable concrete basement. No harder than assembling legos. So, cost is relative, it all depends upon how much you are willing to do yourself.

 

[BoilerMan]

I'll take your word for it, as I only know my one homebuilding experience, but my ICF basement wasn't all that expensive. When I comparison shopped it, everyone told me it would be about 20% more than comparable concrete basements. However, I put in the footing forms (1 day) and built the ICF walls myself (3 days), and it turned out 20% less than a comparable concrete basement. No harder than assembling legos. So, cost is relative, it all depends upon how much you are willing to do yourself.

This is very true, I did all of my home build myself, so labor was not as much of a factor as materials. I had looked into building the entire structure out of ICF, daylight basement and first story with heel trusses on top. With the concrete and pump truck figured in it was prohibitively expensive, but would have been done in 1/8 the time, so that is certainly a factor.

We ran into limestone (ledge) about three feet down when I dug some test pits with a hackhoe. Spoke to neighbors and they had to blast for basements, so that was also a deciding factor.

TS

 

[sinnian]

I'm still convinced that a basement is either the biggest waste of heat if done with plain forms and concrete, or very expensive is done with ICF. I'm a slab man, no water/radon/humidity issues. And I'll never buy a sump-pump as about every home around here has!

The storage would be nice, but not worth the expense IMHO.

TS

Pretty sure radon can go through a "slab" just as easily as it can go through a basement floor.

 

[Fred61]

We ran into limestone (ledge) about three feet down when I dug some test pits with a hackhoe. Spoke to neighbors and they had to blast for basements, so that was also a deciding factor

You made the correct decision not to blast for basement. Ninety percent of the time if your footings, floor or slab is sitting on ledge you will have a water problem whatever soil surrounds the structure or whatever pitch you have away from the house. Water flows on top of ledge. This may be the reason your neighbors have sump pumps.

 

[chken]

This is very true, I did all of my home build myself, so labor was not as much of a factor as materials. I had looked into building the entire structure out of ICF, daylight basement and first story with heel trusses on top. With the concrete and pump truck figured in it was prohibitively expensive, but would have been done in 1/8 the time, so that is certainly a factor.

We ran into limestone (ledge) about three feet down when I dug some test pits with a hackhoe. Spoke to neighbors and they had to blast for basements, so that was also a deciding factor.
TS

I had considered building completely out of ICF as well. As you note, one big advantage is speed. I decided against it because I have a lot of large 5'x5' windows, which means a lot of window bucks and lots of rebar bending, and making sure concrete is flowing into tight spaces, etc. Far easier with SIPs, but I can't do that myself.

One other big advantage of ICFs is that they are very quiet. On a lake where you have fishing boats blasting by and snowmobiles, it can get quite noisy!

Ledge 3 ft down sounds like a blasting job. I hit ledge further down, and hired an excavator with a pick on the end to break it up. I think he was $150 an hour. 3hrs and he was done. No water leakage issues here, then again, the lake level is not that far away. Crossing my fingers.