Zero-energy Attefall. How would you have done it?

[oliven1]

Completely unbroken insulation is practically an impossibility. It's good that you're building carefully, but it's not like the whole concept falls apart due to a few minor thermal bridges. It's the whole that matters. And thermal bridges have absolutely nothing to do with the airtightness of the house. Many small streams, as they say.

no problem at all getting unbroken insulation in an entire wall, no studs or similar needed. Additionally, thermal bridges have a lot to do with airtightness. Minimize thermal bridges, and it becomes incredibly easier to make the building airtight. An airtight building is essential if you want to build a passive house or similar.

 

[Karl-Ove Qvarfordt]

I attended some training regarding passive/zero-energy houses a certain number of years ago and I recall that building small houses with those characteristics was much more difficult than if the houses were larger. I remember that frigge and attefall houses were extremely difficult. But as I said, it's just a faint memory that I'm not so sure about. Surely there is someone here who can correct me.

 

[fribygg]

completely agree, difficult to solve a small log house as a zero-energy house.
that's pretty much what I've been saying all along.

doesn't mean log houses are bad in any way, they have other qualities.

For a house on stilts with as small a living area as TS is considering and which perhaps also won't be permanently heated with electricity, it might be silly to try to build a Zero-energy house with all the precision, technology, and cost that it would entail?

 

[Rabbithole]

no problem at all to get continuous insulation in an entire wall, no studs or similar needed.

then thermal bridges have a lot to do with airtightness.
minimize thermal bridges so it is incredibly much easier to make the building airtight.
and an airtight building is crucial if you want to build passive houses or similar.

Airtightness is definitely important, both from an energy and moisture perspective. Then there are many regular houses with taped plastic that also meet the airtightness requirements for passive houses.

If you have a lot of strange penetrations in the wall, it is of course trickier to seal there, but thermal bridges in the form of wall studs that we are talking about now are not a problem for airtightness.

 

[oliven1]

Absolutely, airtightness is important, both in terms of energy and moisture. Many ordinary houses with taped plastic also meet the airtightness requirements for passive houses.

If you have a lot of strange penetrations in the wall, it's clearly more cumbersome to seal there, but thermal bridges in the form of wall studs that we're talking about now are not a problem for airtightness.

then you haven't really understood how important airtightness is for a low-energy house.
if you build with continuous insulation, you won't have any penetrations that need sealing, so thermal bridges are incredibly important for airtightness.

ordinary houses with standard taping and plastic have no chance of meeting passive house standards or similar. It requires enormous precision both in planning and execution.
There is always special training for the craftsmen who are going to perform this task.

I'm also very interested in why you can't build with continuous insulation in, for example, a wall?

 

[oliven1]

For a house on stilts with such a small living area as TS is considering and that might also not be permanently heated with electricity, it might be unwise to attempt building a Zero-energy house with all the precision, technology, and cost it might entail?

have I said anything else?

it is TS who wanted it, not me?

I have only highlighted the issues with it and passive houses in general.

 

[Rabbithole]

Was at some training regarding passive/zero energy houses a few years ago and I seem to remember that building small houses with those properties was much more difficult than if the houses were larger. I seem to remember that Frigge and Attefall houses were extremely difficult. But as I said, just a faint memory that I'm not so sure about. Surely someone here can correct me.

The heat demand per square meter increases the smaller you build. It is the ratio between the surface area and the floor area that determines it. Then the system losses are also spread over a larger area. However, smaller houses will still have lower total energy consumption. Energy consumption per square meter or per dwelling?

 

[Rabbithole]

then you haven't really understood the concept, how important airtightness is for a low-energy house.
if you build uninterrupted insulation, you won't have any penetrations that need to be sealed, so thermal bridges are incredibly important for airtightness.

ordinary houses with standard taping and plastic have absolutely no chance of meeting passive house standards or similar. It requires enormous precision both in planning and execution.
There is always special training for the craftsmen who will perform this task.

I am also very interested in why you can't build uninterrupted insulation in, for example, a wall?

You are mocking this like some indoctrinated fanatic, yet seem to lack an understanding of the balance of the physical relationships. The more you write, the more you lower your credibility. Just because you build passive houses according to a manual is not proof that you know what you're doing.

At each joint, window, door. The connection of roof trusses, etc. There will always be a small thermal bridge. It is incredibly difficult to avoid. I also strive to build "perfect" and think, for example, that the ventilation ducts should be flow-optimized. But it eventually becomes optimization ad absurdum, and the difference ultimately becomes marginal.

I know that there's a lot of negligence, and you have to maintain the level and exaggerate a bit for the work to be done properly. It's also a good reason not to complicate house construction too much. Design it so it's easy to do it right.

 

[Ulltand]

the insulation should be completely unbroken.
this is how we always build passive houses to meet the requirements of both insulation and tightness.

Or you ensure that the house is sealed with the moisture barrier. I would probably think that it's easier in small houses than in large multi-family buildings.

The heating demand per square meter increases the smaller you build. It's the ratio between the envelope area and the floor area that determines it. Then the system losses are also spread over a larger area. Smaller houses still have lower total energy consumption. Energy consumption per square meter or per residence?

Exactly, and if you use conventional insulation to achieve zero-energy in a 10 sqm friggebod, you'll have 4 sqm of floor space left inside. This is where space materials come into play

 

[oliven1]

You rant about this like an indoctrinated fanatic, yet seem to lack understanding of the balance of the physical relationships. The more you write, the more you lower your credibility. Just because you build passive houses according to a manual, it’s not proof that you have it all figured out.

At all joints, windows, doors. Connections of roof trusses, etc. There is always a small thermal bridge. It’s incredibly difficult to avoid. I also strive to build "perfectly" and think, for example, that the ventilation channels should be flow-optimized. But it eventually becomes optimization to the point of absurdity and the difference becomes marginal.

I know there is a lot of negligence and one must maintain a high level and exaggerate a little for the work to be done properly. It’s also a good reason not to complicate house construction too much. Design it so that it’s easy to do right.

Yes, but all that can be minimized.

A window should absolutely not be mounted against a stud but should be mounted with brackets in the continuous insulation. The frame should be over-insulated. Sealing should be done into the reveal.

The mindset of not complicating things and designing "simply" will never solve the passive house standard. Because it is incredibly complex and requires enormous knowledge both as a designer and installer.

 

[Rabbithole]

Yes, but all of that can be minimized.

A window must not be mounted against a stud but should be mounted with brackets in the continuous insulation. The frame should be over-insulated.
Sealing should be done into the reveal.

The mindset of not complicating and designing "simply" will never solve the passive house standard.
Because it's incredibly complex and requires enormous knowledge both as a designer and assembler.

When I say not to complicate things, I mean complex architectural design. Building simply is smart.

 

[Ulltand]

Yes, but all of that can be minimized.

A window must absolutely not be mounted against a stud but should be mounted with brackets in the unbroken insulation. The frame should be over-insulated.
Sealing should take place inside the reveal.

The mindset of not complicating things and designing "simply" will never achieve the passive house standard.
Because it is incredibly complex and requires enormous knowledge both as a designer and installer.

That may be the case in large projects, but it doesn't mean that it has to be done that way and that there can't be alternatives.

You seem to lack deeper knowledge in building physics. With that knowledge, one can see the impact of different technical solutions and assess them.

 

[fribygg]

You rant about this like a indoctrinated fanatic, yet you seem to lack an understanding of the balance of the physical relationships. The more you write, the more you lower your credibility. Just because you build passive houses according to a manual, it doesn't prove you know what you're doing.

It's as simple as oliven1 not even having built an attefallare, let alone a halftimber house.

 

[oliven1]

That may be how it's done in large projects, but that doesn't mean it has to be done that way and that there can be alternatives.

You seem to lack a deeper knowledge of building physics. If one has that, one can see the impact of different technical solutions and evaluate them.

It's simply that oliven1 hasn't even built a "attefallare", much less a half-timbered house.

unfortunately, you are wrong

 

[oliven1]

That may be how it's done in large projects, but that doesn't mean it's necessary to do so, and there might be alternatives.

You seem to lack deeper knowledge in building physics. With that knowledge, one can see the impact of different technical solutions and evaluate them.

I'm a trained civil engineer, so I would say I have quite good knowledge in building physics.

The problems are the same for both large and small projects.
A window is not more airtight just because it's installed on a small wall?