Fagerdala eps system, what's the catch?

[tib]

Hi!

I'm about to build a house soon and am looking at different options. I've been considering building with Dorocell's Dorotherm system, which is a foam plastic system that you build up like Lego and then pour concrete into a cavity in the middle. The reason for this is partly because the house will have slightly different levels and some of the exterior walls will be rounded, which can easily be achieved with this system (http://www.dorocell.se). I have been in contact with various architects, one of whom has suggested a completely different new system that seems very good http://www.fagerdalaepssystem.se/. This system should be able to handle the same things as Dorocell's but has some advantages, for example, it seems to have better insulation capability, it breathes, and it doesn't burn. Does anyone have any experience or see any obvious shortcomings with this system from Fagerdala?

Regards,

Indecisive first-time builder

 

[anaitis]

An obvious drawback is that the lambda value (insulating capacity) is about 1/3 of that of foam plastic. This means that to achieve the same insulating effect, a fagerdalavägg must be about 3 times as thick as the insulating layer in the foam plastic insulation you are comparing with.

 

[tib]

Thank you for the answer!
However, I'm a bit puzzled because they claim or at least try to show that their house uses very little energy and can go down to about 45kwh/square meter per year.
http://www.fagerdalaepssystem.se/boendeekonomi.aspx

 

[shelby67]

An obvious catch is that the lambda value (insulation capacity) is about 1/3 of that of cellular plastic. In other words, to achieve the same insulating effect, a Fagerdala wall must be about 3 times as thick as the insulation layer in the cellular plastic insulation you are comparing with.

The question can also be applied to a regular wooden house with various thermal bridges, such as studs and other installations, regarding what the actual U-value is.

 

[anaitis]

Thanks for the answer!
I'm a bit puzzled because they claim or at least try to demonstrate that their house uses very little energy and can go down to about 45kWh/square meter per year.
[link]

It's hard to comment without knowing what the rest of the house looks like: Windows, doors, attic insulation.
Also, what do they mean? 45kWh/square meter per year, is that the amount of purchased energy? or consumed? I haven't read everything on their site.

 

[jerk]

I myself built the foundation of our house with Sundolitt KUB, and I have a friend who built his entire house with Dorocell. Dorocell held together better when casting concrete than Sundolitt did. It tended to lift if you were too quick filling in the concrete. Now, Dorocell has come up with a new version that you can screw into. This means you can mount things like gypsum directly against the foam without using the old battens that were mounted during construction. There is a profile embedded in the foam plastic that you screw into, making the wall a more homogeneous concrete wall than its predecessor. I would gladly choose that if I were to build again. You can easily build these yourself. If you're a bit clever when placing the reinforcement, you can cut out the holes for windows afterward.

 

[heintz]

The question could also be asked about a regular wooden house with various thermal bridges, such as studs and other installations, what actual U-value you get

We are in exactly the same situation and have requested a price for a frame with the Fagerdala EPS system for our planned build in Nacka. I must agree that I partially share the concerns about the insulation capability... But I think it seems to be a very excellent building system, went and looked at a house being built and it was a very positive experience! Dry and nice already after a few weeks, even though everything is made of concrete.

It would be interesting if anyone has experience with what an average U-value for a standard wooden wall or light concrete wall is?

 

[anaitis]

Today I noticed yet another possible disadvantage:
The strength is not particularly high. Only 1.8 MPa in compressive strength. This is surely more than enough to bear the wall's own weight, but will require measures where it needs to handle external loads, such as from rafters or beams.
I'm thinking about the actual bearing surface.
It's possible to fix naturally, but it requires consideration.

Additionally, the wall might be somewhat weak when it comes to attaching shelves and similar items.
It requires thought here as well.

 

[jerk]

I think it's interesting with new building methods and materials but I miss pictures on their website. Are there any where you can see what it looks like?

 

[tib]

Hi again!

I have had some contact with a seller at dorocell and sent the following question to him:
"Hi!

Recently got a tip from a friend that there is a new building system called fagerdala eps http://www.fagerdalaepssystem.se/
What makes dorotherm better than fagerdala? I find it hard to compare!"

And the answer I got was:

"Hey!

It's difficult to say exactly but what I can see is well How do you handle electrical installations, what is the u-value, and do you need a crane truck when doing this.

Check that and then feel free to tell me, it's fun to know about new things that come out.

Regards"

On Thursday, I will meet fagerdala's architect and hope to get a bit more answers to the things that have come up here as possible drawbacks.

It's probably as shellby wrote that it's the overall picture you have to consider when it comes to insulating ability, that the wall has a u-value is one thing but the building's entire ability to retain heat must obviously be the most important.

The question is what do you do in a year when you stand there and discover that the electric meter is ticking away at a much faster pace than you had hoped...
Really, you might want to try to contact someone who has built such a house and ask how it works in reality, what costs they got for heating.
I'll check with them on Thursday if I can get some reference projects.

I will get back to you when I've met them.

 

[heintz]

It is hard to say exactly, but from what I can see, how do you handle electrical installations, what is the U-value, and do you need a crane truck when doing this?

I have talked to Fagerdala and you have two options, one is to cast in all electrical wiring, sockets, ventilation, sewage, etc. when they prefabricate the elements. The other option is to mill these in yourself as you would with aerated concrete. Of course, you don't just mill in sewage and larger things in the joists, so the first option is probably preferable.

At the same time, the advantage of milling in, for example, electrical installations is that you get them exactly where you want them, and not where you think they should be based on the drawings, but on the other hand, you can combine the cases. Cast in things where you think they should be and have the ability to adjust at a later stage...

You will need a crane truck, of course, but at the same time, you put up the frame (including the roof) in a couple of days, which you don’t do with the EPS blocks. Another advantage as I see it (I'm sold on this, probably until we get the quote ) is that you don't need to cast the slab in advance. You prepare a gravel bed and the installers lay out the edge beams and then assemble the frame on top of it. When you're done with the frame, you prepare all the installations, etc., that need to go into the slab, and then you pour with 40 cm of EPS-cement. All under the roof! The thickness can be varied depending on the insulation you want.

One disadvantage of this system is that you have to do an overlay casting with self-leveling compound or concrete if you're going to have underfloor heating.

 

[jerk]

What does the price picture look like.

 

[heintz]

What does the price situation look like.

Waiting for a quote, will get back.

 

[shelby67]

I have spoken with Fagerdala and you have two options, one is to cast in all the electrical wiring, boxes, ventilation, plumbing, etc., when they prefabricate the elements. The other option is to mill in such things as you would do, for example, with lightweight concrete. Of course, you don't just mill in plumbing and larger things in the floor slabs, so the first option is probably preferable.

At the same time, the advantage of milling in, for example, electrical installations is that you get them where you really want them, and not where you think they should be based on the drawing, but on the other hand, you can combine the cases. Cast things in where you think they should be and have the option to adjust at a later stage...

You need a crane truck, of course, but at the same time, you raise the frame (including the roof) in a couple of days, which you don't do with the EPS blocks. Another advantage as I see it (I'm totally sold on this, probably until we get the quote ) is that you don't need to pour the slab in advance. You prepare a single bed and the installers lay out the foundation beams and then assemble the frame on top. When you're done with the frame, you prepare all the installations, etc., that need to go into the slab and then you cast with 40 cm EPS cement. All under a roof! The thickness can vary depending on the insulation you want.

A disadvantage of this system is that you have to make an overlay with self-leveling compound or concrete if you want underfloor heating.

Another advantage with their construction is that you avoid having to mix in a bunch of different vapor barriers and others in the wall construction, which can create moisture issues over time, which are otherwise mixed wildly among both stone and wood house manufacturers out there.

 

[tib]

Hello again!

Met Fagerdala on Thursday. They were very nice and seemed skilled, but I think my choice will still be Dorocell. The reason is probably that I'm a bit "timid"; for example, I will want an exterior wall that will be slightly curved, and they hadn't done that before, so I just got a little gut feeling that I'll wait with this system until the next house build when they will hopefully have grown a bit and made more deliveries. However, I like their concept and got to see some houses they had built as well; apparently, they had a house that consumed 45/kW/sqm, which is supposed to be very good, and that house also had quite substantial window sections. I don't know what you might expect to achieve with a corresponding house in 350mm, but time will tell.