GB2257246A

GB2257246A - Air permeable thermally insulating ventilators

Info

Publication number: GB2257246A
Application number: GB9210737A
Authority: GB
Inventors: Samuel Clarke
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-06-21
Filing date: 1992-05-20
Publication date: 1993-01-06
Anticipated expiration: 2012-05-20
Also published as: GB2257246B; GB9113454D0; GB9210737D0

Abstract

A ventilator unit 10 consists of a duct 11 for installation in a cavity wall structure. The duct 11 is formed of a waterproof and thermally-insulating material and contains a body 14 of a vapour-permeable and thermally-insulating material such as an open-cell polymer material. The form of the body 14 permits the passage of water vapour through the duct 11 and minimises the draught through the duct 11. Water is drained through holes 18. The permeable material may be a plurality of thin membranes (34a, 34c, fig 3). <IMAGE>

Description

VENTILATORS This invention relates to ventilators.

The invention is concerned especially, but not exclusively with ventilators for dwelling apartments.

In this description, the term "ventilator" refers to a ventilator unit or "brick", and also to a ventilating portion of a wall structure.

According to the present invention, there is provided a ventilator comprising a duct of a waterproof and thermally-insulating material, and the duct contains a body of a vapour-permeable and thermally-insulating material.

The body permits the passage of water vapour through the duct while minimising the loss of heat. The ventilator is useful in dwelling apartments which are prone to internal dampness and condensation.

Preferably, the intended outer portion of the duct is provided with a vapour-permeable waterproof membrane the inner side of which is spaced from a face of the said body. The membrane may be located inwardly of a protective grill provided on the intended outer end of the duct.

Preferably, also, the-duct is provided with drain-ways for carrying condensate from within the duct to discharge from the intended outer side thereof.

The duct material may be a cellular material of which the cells are of closed-cell configuration.

Alternatively, the duct material is a composite such as fireclay or concrete or a rigid plastics material, such as PVC lined with a layer of insulating material, preferably a closed-cell foam, to minimise condensation within the duct.

Preferably, the said body material is a cellular material of which the cells are of open-cell configuration. A single relatively large body may be provided. Alternatively, one or more sheets of a cellular material, such as sintered polyethylene, may form the body.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a ventilator unit in accordance with the present invention; Fig. 2 is a sectional view to a larger scale than Fig. 1 on the line II-II in Fig. 1 and showing the ventilator incorporated in a wall structure; and Fig. 3 is a sectional view of a ventilator unit in accordance with a further embodiment of the present invention and showing the ventilator incorporated in a wall structure.

In the drawings, the ventilator unit 10 consists of a duct 11 of rectilineal configuration for installation in a cavity wall structure as shown in Fig. 2. The outer end of the duct 11 is provided with a flange 12 for locating abutment with the outside face 13 of the cavity wall.

In Fig. 1, the width and depth of the duct 11 are represented generally by dimensions W and D, and these dimensions will be determined according to the size of ventilator unit required with reference to air-flow.

However, the length of the duct 11, represented by dimension L, is generally standard and equal to the total thickness of the cavity wall.

The duct 11 is made of a rigid closed-cell polymer material which is waterproof and has a high thermal insulation value.

The duct 11 contains a body 14 of a vapour-permeable material which also has a high thermal insulation value. The body 14 is made of an open-cell polymer material produced separately and push-inserted into the duct 11 in the course of manufacture and assembly. Alternatively, the body material is cast in-situ in the duct.

The quantity of body material would be determined by air and vapour diffusion measurements obtained within a range of temperature parameters expected in use.

The outer end of the duct 11 is recessed to accommodate a rectangular frame 15 which secures an air-permeable membrane 16 made of a waterproof material. In Fig. 2, it will be seen that the membrane 16 is spaced from an outer face 14A of the body 14 thus providing an air gap 17 between the membrane 16 and the body 14. Extending through the material of the duct 11, there are provided drain ports or drain-ways 18 for the drainage of condensate from within the duct 11.

The inner end of the duct 11 is recessed to accommodate a frame 19 which secures an inner-end cover 20 made of an open-weave material and which is mainly for decorative purpose.

The general dimensions W and D of the ventilator unit are determined in combination with reference to the air-flow capacity of the body 14 at usual cross-ventilator pressure drops and to provide a value of air changes per hour consistent with any particular application.

The ventilator unit described above is intended for positioning, for example within a dwelling apartment, at a point near the ceiling of such apartment. It is envisaged that such apartment may be provided with a series of ventilators each as described above.

The duct 11 described above is formed of a rigid closed-cell polymer material, though the duct may equally well be formed of a rigid composite or solid plastics material, such as PVC, and such a duct 30 is shown in Fig. 3 of the drawings which illustrates a cylindrical duct located in a cavity wall. In this case, to insulate the duct 30 and minimise the possibility of condensation collecting on the inside of the duct, the duct is also provided with a lining of closed-cell polyethylene foam 32.

Rather than the relatively large volume single foam body 14 described above, this duct 30 is provided with a number of relatively thin (2mm) permeable membranes 34 of sintered polyethylene. This minimises the possibility of condesation collecting on the body which, in severe circumstances, may block the passage of air through the body. To further avoid this risk, the membranes 34 may be treated with a water repellent coating.

A protective grate 36 is provided over the inner end of the duct 30 and a membrane 34a is located inwardly of the grate 36. The grate 36 will provide protection against damage and is also configured to minimise the possibilities of draughts through the duct.

For ventilator units provided in exposed external walls external covers 38 may be provided, such as is illustrated in Fig. 3. The cover 38 is in the form of a PVC box having an open inner wall 40 for communication with the duct 30, and a grated lower wall 42 provided with a open cell membrane 34b. The walls of the box are lined with a closed-cell foam insulating layer 44. A further membrane 34c is also provided between the outer end of the duct and the cover 38.

In modifications of the inventions described above, within the scope of the present invention, the ventilator unit is other than of rectilineal or cylindrical configuration, and may be virtually any configuration capable of manufacture. Also, such modifications envisage the provision of a rigid outer case for the ventilator unit, that is a supporting sleeve fitting to the outside of the duct and made for example from a non-cellular or single phase plastics material. Further, the duct may be formed of a conventional building material such as fireclay or concrete, lined with a suitable insulating material.

Claims

1. A ventilator comprising a duct of a waterproof and thermally insulating material, and the duct contains a body of a vapour-permeable and thermally-insulating material.

2. The ventilator of claim 1 wherein the intended outer portion of the duct is provided with a vapour-permeable waterproofed membrane the inner side of which is spaced from a face of the said body.

3. The ventilator of claim 2 wherein the membrane is located inwardly of a protective grill provided on the intended outer end of the duct.

4. The ventilator of any one of claims 1, 2 or 3 wherein the duct is provided with drain-ways for carrying condensation from within the duct to discharge from the intended outer side thereof.

5. The ventilator of any one of claims 1 to 4 wherein the duct material is a cellular material of which the cells are of closed-cell configuration.

6. The ventilator of any one claims 1 to 4 wherein the duct material is a rigid plastics material lined with a layer of insulating material.

7. The ventilator of claim 6 wherein the insulating material is a closed-cell foam.

8. The ventilator of any one of claims 1 to 7 wherein said body material is a cellular material of which the cells are of open cell-configuration.

9. The ventilator of any one of claims 1 to 7 wherein the body is in the form of a relatively thin sheet.

10. The ventilator of claim 9 wherein a plurality of spaced sheets are provided in the duct.

11. The ventilator of claim 9 or claim 10 wherein the sheet is of a sintered plastic material.

12. The ventilator of any one of claims 1 to 11 further comprising a cover for location over the intended outer end of the duct and having an air-permeable portion provided in a lower wall thereof.

13. The ventilator of claim 12 wherein the cover is formed of a rigid plastics material and said open portion is provided with a vapour-permeable waterproof membrane and the other walls of the cover are lined with a layer of insulating material.

14. The ventilator substantially as described herein and as illustrated in the accompanying Figs. 1 and 2 or Fig 3. of the drawings.