METHOD FOR REMOVING INSULATION FROM THE CAVITY OF A CAVITY WALL

Abstract

 The invention relates to a method for removing insulation from the cavity of a cavity wall, which cavity wall has an inner leaf, an outer leaf arranged spaced apart from the inner leaf, such that a cavity is formed, and an insulation layer arranged between the inner leaf and outer leaf, which method comprises the steps of:
- providing at least one access opening in the outer leaf;
- inserting a length of flexible hose via the access opening into the cavity; and
- supplying pressurized air to the length of flexible hose, causing the length of flexible hose to whip in order to loosen and/or break the insulation.

Description

[0001] The invention relates to a method for removing insulation from the cavity of a cavity wall, which cavity wall has an inner leaf, an outer leaf arranged spaced apart from the inner leaf, such that a cavity is formed, and an insulation layer arranged between the inner leaf and outer leaf, which method comprises the steps of providing at least one access opening in the outer leaf.

[0002] Cavity walls are used to isolate inner walls of buildings from moist and damp penetrating from the outside into the wall. With a cavity wall, the moist and damp penetrates through the outer leaf and is discharge by the airflow going through the cavity between the outer leaf and the inner leaf. This ensures that the moist and damp cannot get to the inner leaf.

[0003] In order to reduce heat loss via the inner leaf to the airflow in the cavity, it has been common since decades to provide an insulation layer in the cavity, preferably arranged in contact with the inner leaf to reduce heat loss from the inside of the building via the inner leaf to the airflow flowing through the cavity.

[0004] It has been found that the insulation material used in the past cannot withstand the test of time. So, currently there is a need to remove the insulation material, such as mineral wool, ureum formaldehyde foam, perlite and expanded polystyrene pellets.

[0005] FR 2582545 discloses a method for removing insulation foam from cavity walls. In this method an access opening is arranged in the outer leaf and a hose with a head is inserted into the outer leaf. Then pressurized air is blown via the head into the cavity and the insulation material is pushed away from the head.

[0006] At a second position, a discharge opening is arranged in the outer leaf for suctioning the insulation material, which is pushed away by the pressurized air. The head rotates such that the jet of air is directed in all directions.

[0007] The disadvantage of this method is that the jet of air only pushes against the insulation material. If the insulation material is too solid, it will not break loose or only when the head is very close to the material. This would require to provide a plurality of access openings in the outer leaf, which in turn will reduce the suctioning of the material, as there will be too much leakage through the plurality of access openings.

[0008] GB 2489767 discloses another method for removing insulation material from a cavity wall. In this method a lance is inserted into the outer leaf. The lance has a jet opening, which directs a jet of air into the cavity and by rotating the lance, a part of the insulation material can be blown away. Then the lance is moved over a small distance and inserted again to remove a next part of the insulation. This also requires a large number of openings in the outer leaf.

[0009] Furthermore the insulation material is only pushed away by air and if the material is too solid or adheres too much to the inner walls of the cavity, it cannot be blown away.

[0010] It is an object of the invention to provide a method for removing insulation material from a cavity wall, in which the above mentioned disadvantages are reduced.

[0011] This object is achieved according to the invention with a method according to the preamble, which method is characterized by:

• inserting a length of flexible hose via the access opening into the cavity; and
• supplying pressurized air to the length of flexible hose, causing the length of flexible hose to whip in order to loosen and/or break the insulation.

[0012] By using a flexible hose and supplying the flexible hose with pressurized air, the flexible hose will automatically start to whip due to the turbulent air in the hose and at the exit opening of the flexible hose. This whipping action of the hose will hit the insulation material in the cavity and provide a direct force on the insulation material causing it to break and to loosen.

[0013] The chunks of insulation material will easily fall down and can be sucked away via discharge openings arranged in the outer wall.

[0014] A preferred embodiment of the method according to the invention further comprises the steps of:

• providing a discharge opening in the outer leaf;
• suctioning loosened and /or broken apart insulation via the discharge opening.

[0015] Preferably, the outer leaf is made of masonry and wherein the discharge opening is provided by cutting out at least one masonry unit, such as a brick or a stone.

[0016] By cutting some of the masonry units, like bricks, out of the outer leaf, a relative large hole is provided along which the loosened and broken away parts can easily be suctioned.

[0017] In yet another preferred embodiment of the method according to the invention the inserted length of flexible hose is partially retracted from or additional length of flexible hose is fed to the cavity, while the pressurized air is fed to the length of flexible hose.

[0018] In fact the length of the flexible hose inside the cavity is varied, while the hose is whipping the insulation material away. This ensures that the insulation material inside of the cavity wall is hit in different positions to break the material and to loosen it.

[0019] In still another embodiment of the method according to the invention a number of access openings is arranged spread over the outer leaf.

[0020] Via each of these access openings, the flexible hose can be inserted, such that the insulation material can be attacked by the whipping action of the hose from different directions.

[0021] Preferably, the access openings in the outer leaf are provided by drilling. This provides for a quick method for arranging the access openings, which is especially of advantage with masonry, in which the openings can be drilled in the joints between the masonry units. After the insulation material has been removed, the cavity wall can easily be filled via these access openings with a new insulation material and then the openings can be almost invisibly filled with joint material. This ensures that the masonry units itself are not affected.

[0022] These and other features of the invention will be elucidated in conjunction with the accompanying drawings.

Figure 1 shows a perspective view with cut away portions of a cavity wall on which the method according to the invention is applied.

Figure 2 shows a cross sectional view of the cavity wall of figure 1.

Figure 3 shows a front view of the insulation layer and inner leaf of the cavity wall according to figure 1.

[0023] Figure 1 shows a cavity wall 1 with an inner leaf 2, an insulation layer 3 arranged on the inner leaf 2 and an outer leaf 4 spaced apart from the inner leaf 2, such that a cavity 5 is formed.

[0024] The outer leaf 4 is masonry build out of masonry units 6, in particular bricks. An access opening 7 is drilled into the outer leaf 4 through which a flexible hose 8 is fed. A length 9 of flexible hose 8 extends in the cavity 5 and when pressurized air A is fed to the hose 8, the air will exit at the open free end 10 of the length 9, causing the length 9 of flexible hose 8 to whip.

[0025] The whipping action of the length 9 of flexible hose 8, will hit the insulation layer 3, such that particles 11 will break loose (see figure 2) and a opening 12 will be formed in the insulation layer 3.

[0026] Furthermore, a discharge opening 13 is cut in the masonry of the outer leaf 4, along which the particles 11 can be suctioned along a suction pipe 14.

[0027] Figure 3 shows a front view of the insulation layer 3 and inner leaf 2 of the cavity wall 1. When pressurized air A is fed to the length 9 of flexible hose 8, the length 9 will start to whip in random direction, hitting the insulation layer 3 and causing particles 11 to break loose, which can be suctioned via the discharge opening 13. This provides for an effective way of removing the insulation layer 3 from the cavity wall 1.

Claims

1. Method for removing insulation from the cavity of a cavity wall, which cavity wall has an inner leaf, an outer leaf arranged spaced apart from the inner leaf, such that a cavity is formed, and an insulation layer arranged between the inner leaf and outer leaf, which method comprises the steps of:

- providing at least one access opening in the outer leaf;

characterized by

- inserting a length of flexible hose via the access opening into the cavity; and

- supplying pressurized air to the length of flexible hose, causing the length of flexible hose to whip in order to loosen and/or break the insulation.

2. Method according to claim 1, further comprising the steps of:

- providing a discharge opening in the outer leaf;

- suctioning loosened and /or broken apart insulation via the discharge opening.

3. Method according to claim 2, wherein the outer leaf is made of masonry and wherein the discharge opening is provided by cutting out at least one masonry unit, such as a brick or a stone.

4. Method according to any of the preceding claims, wherein the inserted length of flexible hose is partially retracted from or additional length of flexible hose is fed to the cavity, while the pressurized air is fed to the length of flexible hose.

5. Method according to any of the preceding claims, wherein a number of access openings is arranged spread over the outer leaf.

6. Method according to claim 5, the access openings in the outer leaf are provided by drilling.

Drawing