Are log cabins good at keeping in the heat?

[hearthon]

Simply out of curiosity and a recent discussion between me and a friend, are these cabins any good at keeping the heat in? The wood looks like it's a 3x6 and I'm just wondering how it would do with a wood stove inside. I guess if the cabin dosent keep the warm air in you could always buy a bigger stove.... just wondering if anyone has any input.

 

[bholler]

Simply out of curiosity and a recent discussion between me and a friend, are these cabins any good at keeping the heat in? The wood looks like it's a 3x6 and I'm just wondering how it would do with a wood stove inside. I guess if the cabin dosent keep the warm air in you could always buy a bigger stove.... just wondering if anyone has any input.


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The wood isn't terrible insulation but they are most often terribly drafty

 

[salecker]

The logs act as thermo mass
I know up here in the north a log cabin will not freeze inside as quick as a stick framed house.
The logs will give up the stored BTU's to keep the frost at bay.

 

[stoveliker]

Apart from the air tightness (draft), the R-value of the best (insulating) wood is about 1.5 per inch. Other wood is below 1 per inch.
So if the wall is 6" thick (not uncommon for log cabins I have seen), the R-value of a wall will be 9 at most.
That is a lot less than a 2x4 + fiberglass wall.

It's not nothing though.

 

[EatenByLimestone]

If you can seal between the logs and keep the place warm all the time they aren’t bad. If you’re trying to take it from below freezing ambient temperature quickly you’re going to hate trying to heat the thermal mass.

 

[begreen]

The wood isn't terrible insulation but they are most often terribly drafty

That really depends on the sealing between log layers (chinking) and joints. Done well, they are not drafty. The problem many have is wood shrinkage. If the chinking is traditional, then in will likely need redoing after several years. Many modern log cabins have workarounds for this issue using modern milling techniques for tighter fit, splines, and compressible foam insulation. How well this sealing stands up over time is TBD.

The wood itself is not the best insulation, but better than a cement or stone wall. My wife grew up in a log house that was an inn. It was hard to heat, but once up to temp it stayed reasonably warm. It takes a lot of heat to warm up all the thermal mass of the wood but once that mass is heated, it stays warm a long time. Just don't let it get too cold.

 

[EatenByLimestone]

Oh, log homes are very inviting to wood boring insects and bats. If you are aware of the issues going in, it’s not bad, but many people aren’t aware until too late!

 

[bholler]

That really depends on the sealing between log layers (chinking) and joints. Done well, they are not drafty. The problem many have is wood shrinkage. If the chinking is traditional, then in will likely need redoing after several years. Many modern log cabins have workarounds for this issue using modern milling techniques for tighter fit, splines, and compressible foam insulation. How well this sealing stands up over time is TBD.

The wood itself is not the best insulation, but better than a cement or stone wall. My wife grew up in a log house that was an inn. It was hard to heat, but once up to temp it stayed reasonably warm. It takes a lot of heat to warm up all the thermal mass of the wood but once that mass is heated, it stays warm a long time. Just don't let it get too cold.

We have quite a few in this area that ended up being wrapped and sided because after shrinkage they just couldn't keep drafts under control

 

[EatenByLimestone]

I’ve gone row by row on them sealing between logs. It wasn’t fun, or cheap. Thank God for battery powered caulk guns.

 

[begreen]

I’ve gone row by row on them sealing between logs. It wasn’t fun, or cheap. Thank God for battery powered caulk guns.

My wife's father was a mason. He did a great job of redoing the chinking on the inn. It was built during the depression out of chestnut logs that had fallen during the blight of that era.

 

[hearthon]

Ya I've been reading that the r value is low but they act as thermal mass so it's different. Would love to stay in one during the winter so see how it behaves.

 

[Wisco Shepherd]

Ya I've been reading that the r value is low but they act as thermal mass so it's different. Would love to stay in one during the winter so see how it behaves.

This is true, I think just looking at R values doesn't capture the whole picture.

 

[bholler]

Ya I've been reading that the r value is low but they act as thermal mass so it's different. Would love to stay in one during the winter so see how it behaves.

But thermal mass without r value doesn't do you much of any good. The heat still goes through it

 

[Wisco Shepherd]

But thermal mass without r value doesn't do you much of any good. The heat still goes through it

True didn't think about it that way. I have some friends with well chinked log cabins and they swear they are easy to heat and have less swings but all of that is purely anecdotal.

 

[stoveliker]

The point of thermal mass is that it takes a lot of energy to heat up a (pound of) material by a degree - and thus slow down the heating up of a home when a stove is started (and slow down the cooldown when the stove goes cold). The scientific term is heat capacity.
The point of the R value is to inhibit heat transport.

High thermal mass materials in a wall will help even out temperature fluctuations, but when they are warm, they are continuously shed BTUs to the great outdoors at a rate determined by their R-value. The R-value is not great (but not exceedingly low either) for wood.

High thermal mass materials are therefore best applied within an insulation envelope. And that is the concept of a masonry (mass) heater located within a home.

Hence, to avoid loosing many BTUs to the outdoors with a log cabin, an insulation envelope should be present on the outside of the log cabin. But that kills the aesthetics (which are great, see the pics above).

So it's a choice of what you value more.

 

[Todd]

My log cabin has 10” Swedish cope logs. There is a strip of foam insulation between the logs and special log caulk between the seams inside and out. My first Winter I was chasing leaks especially in the corners. I think the logs are pretty much settled and I haven’t found any leaks or feel drafts anymore.

The thermal mass of the logs have a big effect in Winter and as well as Summer. Once the logs are warmed up they stay warm for a long time and help even out the heat. if they are cold it will take a few hours to bring them up to temp. Summertime I find the cabin stays cooler than my previous stick built home unless I have a long stretch of 90 degree weather I really don’t need the A/C on.

 

[begreen]

Hence, to avoid loosing many BTUs to the outdoors with a log cabin, an insulation envelope should be present on the outside of the log cabin. But that kills the aesthetics (which are great, see the pics above).

We looked into this years ago. There is a cheat. Half logs skinning a internal ICF or similar wall. On the outside and inside it looks traditional, but one loses half of the thermal mass this way. Done right, they are tight, easy to heat buildings. One of these designs is the Thermal-Log building system.

 

[stoveliker]

We looked into this years ago. There is a cheat. Half logs skinning a internal ICF or similar wall. On the outside and inside it looks traditional, but one loses half of the thermal mass this way. Done right, they are tight, easy to heat buildings. One of these designs is the Thermal-Log building system.

Obviously a "sin" for traditionalists

 

[begreen]

Obviously a "sin" for traditionalists

True, but the insulated core is not visible if done right so don't ask, don't tell.

I think the days of hand hewn logs has passed for most. There are now insulated concrete timber homes that look pretty good too.
(broken link removed)

 

[vatmark]

We live in a log home. We love it. We live in NC so we do not get the crazy low temps like other areas. It is not a chinked log cabin. We do not heat exclusively with wood. We have heat pumps. But when we use our wood stove it gets the main level of our home(1800 sq ft) nice and toasty. We do not pack the stove full. There have been times when we need to open the sliding glass doors because it gets too warm for our taste. It seems to hold the heat pretty well. We do not burn overnight. We let the fire burn out before bed. It is still usually 70 on our main level at 4am. When we wake in the morning the heat pump has kicked in. We have a Jotul Oslo V2.

 

[begreen]

Nice looking home and stove! Is there a spline sealing between each log layer?

 

[vatmark]

Nice looking home and stove! Is there a spline sealing between each log layer?

Nope. When we first moved in when there were strong winds some saw dust would fall out of the logs in a few spots. It is certainly not energy efficient. I think if we would have done more research we would have looked more into sealing of non chinked log cabins. The logs are tongue and groove D logs.

 

[stovelark]

Beautiful setup Vatmark- in a nice temporal area of the country too. We still are in SE CT, but hope to in a few years move to the Carolinas or Georgia. Hopefully there will still be spots left.

 

[panderson03]

My log cabin has 10” Swedish cope logs. There is a strip of foam insulation between the logs and special log caulk between the seams inside and out. My first Winter I was chasing leaks especially in the corners. I think the logs are pretty much settled and I haven’t found any leaks or feel drafts anymore.

The thermal mass of the logs have a big effect in Winter and as well as Summer. Once the logs are warmed up they stay warm for a long time and help even out the heat. if they are cold it will take a few hours to bring them up to temp. Summertime I find the cabin stays cooler than my previous stick built home unless I have a long stretch of 90 degree weather I really don’t need the A/C on.

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Our cabin is built by tightly-pinned-butt & pass. Our experience is the same. Our place stays cool so well during summer that we don't even have AC. We do take advantage of our whole-house fan to cool down our thermal mass all night long to help keep our place cooler during hot days. Our logs average 12 inches in diameter

 

[vatmark]

Beautiful setup Vatmark- in a nice temporal area of the country too. We still are in SE CT, but hope to in a few years move to the Carolinas or Georgia. Hopefully there will still be spots left.

Thanks. Both my husband and myself were raised in NJ. We got the heck out of there 28 years ago. Too expensive.