[0001] The invention relates to a method of improving the thermal insulating ability of
a building construction that has a layer of a thermal insulating material, wherein
a diffusion stonping layer is used inside of the insulating material and a wind stop
is used outside of the insulating material.
[0002] The thermal insulation is reduced in rior art constructions since the constructions
are not tight enough. Light constructions in particular tend to be untight in the
long run because of the continaual variations in outdoor temperature and humidity.
For example, hard board sheets nailed to a wooden framework tend to be untight in
the joints because of the thermal and humidity movements in the board itself. It should
also be noted that a brick wall, whether used as tne bearing wall or as a panel, is
not sufficient as a wind stop because of it pores. Therefore also in prior art constructions
where material with excellent thermal insulating properties are used, for example
mineral wool, the thermal insulation is not very good due to the lack of tightness.
[0003] Thus, it is an object of the invention to provide for an improved thermal insulation.
This is accomplished by improving the tightness defined in the claims.
[0004] The invention will further described with reference to tne accompanying drawings.
Figure 1 is a schematic and fragmentary section tnrougn a new 1
storey nouse to whcih the invention is applied.
Figure 2 s ov-s details of Fig. 1 on a larger scale.
Figure 3 shows a roof truss that is also partly shown in Fig. 1.
Figure 4 is a schematic and fragmentary section through an existing house to which
the invention is applied during reconditioning.
Figure 5 shows details of Fig. 4 on a larger scale.
Figure 6 shows a connection stripused to tighten against door and window frames.
Figure 7 shows a collar for electric joint boxes.
Figure 8 shows an end strip used to- tighten against a wall.
[0005] Fig. 1 shows schematically the invention applied to a new house in light construction,
that is, a house with wood frame work walls and a layer of mineral wool between the
wood battens of the frame work. The house has a foundation in the form of a concrete
slab that rests on a layer of a non-illustrated thermal insulating material on the
ground. The frame work of the walls is not shorn. A roof truss 14 is shorn separately
in fig. 3. It comprises raf.ters 15, a tie 16 and a top batten 17. The rafters do
not extend outside the walls and they do not make the roof top, but the roof is a
separate construction that rests on the rafters 15 and forms the eaves 13 and the
roof top 18. Wind stonping paper is attached to the roof truss 14 around the tie and
the rafters at their connection and sealingly cemented to a strip 20 of paper.
[0006] Wind stopping paper 22 from a roll is mounted by means of staples to the outside
of the frame work of the walls and roof, i.e. outside of the mineral wool 21. The
strips of the wind stopping paper 22 overlap and the strips are stitched so that the
staples are covered by the overlap of the next strip. All the joints are tightened
by jointing paper tapes that have one side coated with a thermal cement so that they
can be affized to the wind stopping paper by means of an electric iron. The cement
is not adhesive before being heated. The rind stopping paper 22 is shown with dash
lines in the figures. The unconventional construction of the trusses permits the wind
stopping paper 22 of the walls and of the roof to be integral without rafters extending
through the paper which reduces the risk of untightness. The wind stopping paper is
cemented to the paper strips of the trusses by means of jointing tape as previously
described.
[0007] Inside of the mineral wool 21, that is, on the inner side of the frame work of the
walls and roof,a diffusion stopping paper 23 (the steam stop) is mounted in the same
way as the rind stopping paper (the wind stop). The diffusion stopping paper 23 is
shorn with dash-and-dot lines. This diffusion stopping paper 23 is tightly cemented
to the paper around the raffers 15 and ties 16 by means of jointing tape 25 in the
same way as previously described. The window frames and door frames and possible other
frames are mounted to the frame work before the two paper layers 22,23 are mounted.
In fig. 1, a window frane 24 is shown. Before the frames are mounted, a connection
strip 25 of paper is attached to each frame by means of laths 27 that are nailed to
the frame as shown in fig. 6. The connection strip 25 has a wide rubber sealing list
that has sealing portions 28,29 on both sides of the nails. The frames are affixed
to the frame work by the laths 27 that are nailed to the frame work. When the diffusion
stopping paper 23 and the wind stopping paper 22 are mounted as described above, the
connection strip 25 of the frame 24 is cemented to both these paper layers by means
of a jointing strip 30 of the kind used also for jointing the paper strips as described.
The paper of the connection strip 25 around the frame 24 has to be cut at the corners
in order to permit for it to be bent against the papers 22,23, and these cuts are
lapped by 'pieces of the jointing strip. A layer of diffusion stopping paper 31 is
suitably put on the concrete slab 11 if an overfloor c nstruction (non-illustrated)
is to be laid on the slab. A comparatively thin layer of mineral wool 32 may or may
not be used in the overfloor construction above the diffusion stopping paper.
[0008] It is important that there are no leaks neither in the wind stopping layer nor in
the diffusion stopping layer. Therefore, one must seal off very carefully against
all elements extending through one or both stops 22,23. A pre-fabricated collar 33
of paper can be used for electric joint boxes, pipes etc. It is cemented against the
diffusion stopping paper by means of a jointing strip 30 of the kind previously described
and its collar 34 of crepe paper is sealed off against the box by means of a tightening
band 35.
[0009] As shown in Figs. 1-3 and described above, walls and roof will be enclosed by a completely
tight wind-stopping layer, the paper 22. Further, the layer of mineral wool 21 will
be completely tightly 'enclosed between this wind stopping paper 22 and the diffusion
stopping paper 23. The diffusion stopping paper 23 should be 10 times more diffusion
stopping than the paper 22 when the construction is completely airtight as illustrated
in order to avoid moisture in the mineral wool. Laths are nailed on both sides of
the illustrated construction, that is, outside of the papers 22,23 and the outer and
inner panel can be nailed to the latns. A sealing list of tne kind shown in fig. 6
can be placed under the laths on tne outside of the wall in order to seal off around
tne nails. Tne panel need not be afiixeu to the wall construction, a more or less
free standing brick wall can be used as a panel.
[0010] As described, paper is only cemented against paper. It would be possible to cement
the paper 22 directly to the outside of the window frame 24 in Figs. 1-2 and cement
the paper 23 directly to the inside of the frame 24. It is, however, likely that a
cemented joint between paper and wood does not last as long as a cemented joint between
paper and paper. It will be possible to guarantee the tightness of a joint between
paper and paper for a period of 50 years if a suitable cement is used.
[0011] In fig. 4. an example is shown of the possibility of applying the invention to an
existing building when the walls are insulated on their outside. In this case, there
is mostly not possible to join the diffusion stop in the walls with the diffusion
stop in tne roof, neither is it possible to join the wind stop in the walls with the
wind stop in the roof even when walls and roof are insulated at the same time.
[0012] The additional insulation of the walls are carried out as follows
[0013] If the wall has a removable outer panel, the panel at shall first be removed. Then,
diffusion stopping paper 23 is mounted on the existing wall and battens are nailed
or secured in any other way to the vail. Mineral wool is now put in place to completely
fill the space between the battens. Outside of the mineral wool, a wind stopping paper
22 is altached to the baltens and sealingly connected to tne difiusion paper at the
end of the mineral wool at the roof and at the foundation. Further, the insulation
construction is sealed off against tne existing wall by means of sealing strips as
indicated with numerals 57 and 30 on Fig. 5. A sealing strip 25 of the kind shown
in fig. 6 has been used at 37 and it is affixed to the existing wall by means of a
nailed lath-27. The strip 25 is cemented by means of jointing strips 30 to the two
paper layers 22 and 23. All joints are cemented to be tight as previously described.
[0014] At the bottom of Fig. 5, a sealing strip 39 has been used at 38. It is also shown
in fig, 8 and it comprises a strip of wind stopping paper 40 to which is cemented
a closed pocket 41 of crepe paper. The pocket is filled with elastic mineral wool
42 that acts as a spring to expand the pocket so that the crepe paper seals also against
uneven surfaces. The sealing strip 39 at 38 in fig 5 is clamped together with a strip
43 of wind stopping paper against the existing wall by means of a nailed lath 48.
The strip 43 is cemented to the layers 22 and 23 by means of jointing tape 30 in the
same way as previously described so that the mineral wool insulation will be completely
tightly enclosed.
[0015] In order for insulating the floor that is shown as a joist construction above a ventilated
space towards the ground, the old flooring and the old insulating material is removed.
Then, wind stopping paper 22 is laid in the bottom around all the joists 44 and up
along the wall where an end strip 45 for instance of the kind shown in fig. 8 is used
to seal against the wall. The wind stopping paper is carefully tightened in all joints
by means of jointing strips as previously described. Then, the mineral wool or other
insulation is placed between the joi sts and a diffusion stopping paper 23 is placed
above the insulation. The paper 23 is also jointed by means of jointing strips to
a completely tight layer that is jointed to the wind stopping paper by means of a
jointing strip 30 as shown in fig. 5. The mineral wool of the floor will therefore
also be completely tightly enclosed by the wind stopping paper 23 and the diffusion
stopping paper 22.
[0016] The roof is insulated in the same way as the floor and the wind stopping paper 23
is sealed off against the wall by means of a strip 46 of the kind shown in fig. 8.
[0017] The ending strips 45 and 46 are suitably so placed as to be covered by the ceiling
list and floor list respectively. In combination with the wall lining, for example
wall paper, they provide an additional draft preventing layer that prevent draft through
the existing wall.
[0018] An open clearance that should always be between the wind stopping layer and the roof
is indicated by arrows in fig. 5 as well as in fig. 2.
[0019] In a new building with a bearing wall in a heavy construction, for example a brick
wall, the insulating construction is preferably mounted on the outer side of the wall
in the same way as shown in Figs. 4 and 5. The wind stopping paper of the walls and
the roof should then be united in the same way as shown in Figs. 1 and 2.
[0020] In the figures, the wind stopping layer and the diffusion stopping layer has been
shown as being of strong tough paper. Alternatively, hard board sheets can be used
if their joints are tightened by means of jointing strips of the kind described.
1. Method of improving the thermal insulating ability of a building construction that
has a layer of a thermal insulating material, wherein a diffusion stopping layer is
used inside of the insulating material and a wind stopping layer is used outside of
the insulating material,
characterized in that
the diffusion stopping layer as well as the wind stopping layer is cemented in its
joints and that the two stopping layers are connected to completely sealingly enclose
the thermal insulating layer between them.
2. Method according to claim 1, characterized in that the diffusion stopping layer
or the wind stopping layer is sealed off against the building construction at the
place where the respective layer begins or ends.
3. Method according to claim 1 or 2, characterized in that the two stopping layers
are united by being cemented together.
4. Method according to any one of the preceding claims, characterized in that a connection
strip is sealingly affixed to a frame of a window, door or the like or to the construction
andthat the two stopping layers are air tight cemented to the connection strip.
5. Method according to claim 4, characterized in that a connection strip is used which
comprises a sealing list that is clamped against the frame or construction.
6. Method according to claim 5, characterized in that the sealing list is clamped
against the frame or construction by means of nailed laths.
7. Method according to claim 6, characterized in that a sealing list is used that
has a sealing function on both sides of the nails in the lath.
8. Method according to any one of the preceding claims, characterized in that paper
coated with a thermal cement and an electric iron are used for tightening joints in
the layers.
9. Method according to any one of the preceding claims, characterized in that paper
is used both as wind stopping layer and diffusion stopping layer.