A garden shed makes staying in the garden pleasant. The more intensive the use, the higher the quality of the stay should be. We explain how to effectively insulate the roof, floor and facade.
Table of Contents
Principles of isolation
Once you have decided to insulate your garden shed in the countryside , the most difficult question is probably that of sensible, easy to implement and, last but not least, appropriate measures. In order to be able to weigh things up correctly, you must first know what is important when insulating:
- Minimizing heat transfer through external components
- Reduction of thermal bridges, i.e. particularly permeable detail points
- Reduction of drafts to reduce cooling and prevention of mold damage
- Creation of a coherent system of surface insulation and special areas such as windows and doors
- Development of an appropriate relationship between insulation effort and savings success
Insulate outside or inside?
Generally speaking, there are two ways to provide your garden house with thermal insulation. You can either provide the existing construction with the desired insulating layer on the inside or on the outside. Especially with garden houses, each variant offers its own advantages and challenges:
interior insulation
- Weather protection provided by the building envelope remains
- Insulation of lower resistance can be used
- in the case of components in contact with the ground, this is usually the only practical option
- Reduction of usable interior space
- Effort to keep walls stable or floors accessible despite insulation for wall shelves etc., for example
- Installation often under difficult conditions due to limited space in the hut
external insulation
- no change in the equipped interior
- can be easily combined with existing training (“anyway” work)
- Better accessibility of components that come into contact with outside air
- Weatherproof shell needs to be rebuilt
- Higher risk of condensation forming between, for example, the wall and the external insulating layer
- In the case of components in contact with the ground, this can only be implemented with a great deal of effort
Typical measures for each component
Now let’s take a closer look at the sensible ways to insulate your garden house. The most common methods are described, but they may have to be adapted in detail to the special features of your house.
Which insulation material?
If you think of insulation work on residential or other “high-quality” buildings, a whole range of different insulation materials will certainly come to mind. Not all of them are suitable for insulating your garden house, as they are either very expensive or have high demands in terms of construction and installation details. Ultimately, there are very few common materials that are both technically well suited and reasonably priced:
Expandiertes Polystyrol EPS
This foam plastic is known under its trivial name Styrofoam. The insulating material is cheap, very easy to process as a panel material and at least moderately compressive. However, Styrofoam absorbs moisture over time and tends to mold and rot.
Extrudiertes Polystyrol XPS
This plastic foam is known, for example, as Styrodur. Slightly more expensive than Styrofoam, the insulation boards are insensitive to moisture and water and can therefore also be used outdoors with UV protection. In addition, some types of this material allow very high pressure loads, which makes it particularly advantageous to use it as insulation on the floor.
mineral wool
Mineral fiber insulating materials, also known as stone wool, score particularly well with their good adaptability and high flexibility. On the other hand, mineral wool is hardly mechanically resilient. Typical uses of this insulating material are therefore insulating measures between existing structures, such as rafters, etc., where large cut insulating mats can be pressed in without any problems and also adapt to unevenness by themselves.
The roof
The roof is the most exposed and also the largest individual component of your garden house. Therefore, the insulation effort is particularly worthwhile here.
The interior insulation
Variant 1 – insulation between rafters
Insulation material: mineral wool
Action:
- Measure clearances between existing rafters
- Cut mineral wool lengths to size with a few centimeters extra width
- then press in the insulating sheets between the rafters
- Nail the slats to the underside to prevent them from falling out across the rafters and over the insulating sheets
Variant 2 – sub-roof insulation
Insulation material: EPS
Action:
- Clean flat roof constructions, eg trapezoidal sheet metal or slab roofs without rafters
- Cut the styrofoam panels to size and glue them to the roof structure from below using a suitable construction adhesive
- Join boards tightly and avoid cross joints (staggered installation)
- After the adhesive has hardened, fill any defects caused by unevenness etc. with a suitable insulating foam or swelling adhesive
The roof insulation
Insulation material: XPS
Action:
- Clean existing roof surface
- Remove loose seals such as foil, roofing felt, etc
- Lay out and glue the insulation boards flat and tightly butted on the roof
- Screw the insulation boards with plate dowels downwards into the roof skin according to the manufacturer’s instructions
- Cover the edges of the roof, for example, with planks or metal sheeting
- Rebuild roof covering from sheet metal, foil, roofing felt
The floor
The ground has the great advantage that the ground also cools down, but never reaches such low temperatures as the outside air. Therefore, insulation measures in the garden house can be significantly less than on the facade or roof.
Bearing wood with insulation insert
Insulation material: mineral wool / EPS
Action:
- Clear and clean the floor
- Lay out waterproof foil against rising ground moisture and stick to the side of the walls
- Lay out wood (at least 6 cm wide) in the thickness of the insulation layer, spacing approx. 60 centimetres
- Fill in the gaps with insulating material
- Screw load-bearing chipboard or OSP boards to joists as a new floor covering
Flameproof insulation
Insulation material: XPS
Procedure: as for the execution of the joists, but instead of the joists, the insulation boards are laid over the entire surface, the floor covering is laid floating and the boards are only glued/screwed to one another
The facade
Because of the design demands that are usually placed on a building facade, even in the case of a garden house, this task is probably the most difficult.
The interior insulation
Insulation material: mineral wool / EPS
Action:
- clear walls
- Align the joists vertically with the thickness of the insulation layer and screw them to the wall
- Distances ideally in insulation board / insulation sheet width
- Wood width at least 4 cm for screwing the later covering
- Fill in the gaps with insulating material
- Screw chipboard or OSB boards flat onto joists
The outside insulation
If, on the other hand, you want to insulate your garden house on the outside, proceed in the same way as described for the interior insulation. However, you should choose the joists at least 2 centimeters higher than your planned insulation layer. This allows air to circulate between the insulation and the facade and transport moisture away. Depending on your taste, you can apply facades made of wooden boards or trapezoidal sheet metal or even plastic to the joists.
