Insulating Summer House for Winter
Hello,
Apologies for the use of English, my partner and I are moving to Sweden this summer from Australia and I am in the process of learning the Swedish language.
We have purchased a property with 2 summer houses and we will be winterizing each one alternatively. We will start with the cottage built in 1991 to have it ready for Winter 2024. It is of Timber construction, with I assume currently has simple insulation. I have not seen the house in person. It is located in Kalmar Lan, Snowzone 2.5 KN/M2.
Can I please ask advise on the following:
1. External Walls, what is the best way to increase the insulation value? What depth will the current studs most likely be? (removal of external boards is ok as we are doing the labour ourselves)
2. Roof/ceiling, what is the best way to increase the insulation value? (removing roof cladding in order to gain access)
3. Plinth foundation/floor, there is currently no insulation and moisture level is above acceptance in some parts. We may consider concrete slab floor installation but are not opposed to an upgraded plinth floor if acceptable insulation can be achieved?
Thankyou in advance, Bamish
1991 cottage:
Apologies for the use of English, my partner and I are moving to Sweden this summer from Australia and I am in the process of learning the Swedish language.
We have purchased a property with 2 summer houses and we will be winterizing each one alternatively. We will start with the cottage built in 1991 to have it ready for Winter 2024. It is of Timber construction, with I assume currently has simple insulation. I have not seen the house in person. It is located in Kalmar Lan, Snowzone 2.5 KN/M2.
Can I please ask advise on the following:
1. External Walls, what is the best way to increase the insulation value? What depth will the current studs most likely be? (removal of external boards is ok as we are doing the labour ourselves)
2. Roof/ceiling, what is the best way to increase the insulation value? (removing roof cladding in order to gain access)
3. Plinth foundation/floor, there is currently no insulation and moisture level is above acceptance in some parts. We may consider concrete slab floor installation but are not opposed to an upgraded plinth floor if acceptable insulation can be achieved?
Thankyou in advance, Bamish
1991 cottage:
I’m sorry, but I can’t give you the advice you’re asking about. Maybe you can find some information on “energimyndigheten”,konsumentverket or at the local “konsumentrådgivare”. The latter you find in the district (kommunen), where your cottage is situated. Somebody there should be able to help you.
Late answer, but still...
You may contact the "byggnadskontor" or some similar name in the community ("kommun") where the cottages are. They should have construction drawings which you can request copies of. It would be helpful to know how the houses actually are constructed and insulated.
What is the purpose of the winter insulation? To be living in the houses permanently? Or renting them to tourists, or using them as all-year-around overnight cottages for friends and family?
The purpose sets the standard of the houses. For temporarily overnight stay a bit less insulation and other qualities might suffice.
For permanently living a reasonable insulation thickness of the walls would be 15-20 cm. Thicker walls (around 25 cm) are used in new built houses, but it is not really practicle for older houses or summer houses. Nor does it make much difference in energy consumption, and certaintly not in the southern part of Sweden.
Roof insulation is usually some cm thicker, but most of the extra thickness is because the insulation is blown up and therefore does not have any windstopper on top. To effectively block any movement of airstreams (internal as well as external) is crucial for glass-/stonefibre insulation to actually reach its theoretical insulation effectivity.
Also, it is important to remember keeping tabs on the moist. You do not want moisture condensing inside anywhere of the construction, ie floor, walls, or roof.
The floor should be easy to add insulation if there is not any right now. However, it seems strange if a house built in the 90-ties have no insulation in the floor, even for a summer house. It is normally constructed with wooden beams and insulation inbetween, Thicknesses 15-22 cm. Your house is probably in the lower end, but it is easy to add a layer of insulation underneath, provided there is enough space between the floor and the ground.
With more details on the house(s), and use purpose you will probably get more detailed recommendations. The knowledge and experience is definitively present in this forum, and the language should not be that big an issue I think.
You may contact the "byggnadskontor" or some similar name in the community ("kommun") where the cottages are. They should have construction drawings which you can request copies of. It would be helpful to know how the houses actually are constructed and insulated.
What is the purpose of the winter insulation? To be living in the houses permanently? Or renting them to tourists, or using them as all-year-around overnight cottages for friends and family?
The purpose sets the standard of the houses. For temporarily overnight stay a bit less insulation and other qualities might suffice.
For permanently living a reasonable insulation thickness of the walls would be 15-20 cm. Thicker walls (around 25 cm) are used in new built houses, but it is not really practicle for older houses or summer houses. Nor does it make much difference in energy consumption, and certaintly not in the southern part of Sweden.
Roof insulation is usually some cm thicker, but most of the extra thickness is because the insulation is blown up and therefore does not have any windstopper on top. To effectively block any movement of airstreams (internal as well as external) is crucial for glass-/stonefibre insulation to actually reach its theoretical insulation effectivity.
Also, it is important to remember keeping tabs on the moist. You do not want moisture condensing inside anywhere of the construction, ie floor, walls, or roof.
The floor should be easy to add insulation if there is not any right now. However, it seems strange if a house built in the 90-ties have no insulation in the floor, even for a summer house. It is normally constructed with wooden beams and insulation inbetween, Thicknesses 15-22 cm. Your house is probably in the lower end, but it is easy to add a layer of insulation underneath, provided there is enough space between the floor and the ground.
With more details on the house(s), and use purpose you will probably get more detailed recommendations. The knowledge and experience is definitively present in this forum, and the language should not be that big an issue I think.
And remember that if you decide to put extra insulation on the outside of the walls you will probably need a building permit. Contact the local building committe of your municipality ("byggnadsnämnden" in your "kommun").