GB2257175A

GB2257175A - Securing damp proof membranes.

Info

Publication number: GB2257175A
Application number: GB9114544A
Authority: GB
Inventors: Peter Archibald Knott
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-07-05
Filing date: 1991-07-05
Publication date: 1993-01-06
Anticipated expiration: 2011-07-05
Also published as: GB2257175B; GB9114544D0

Abstract

A device (14) for securing a damp proof membrane (16) in a building to a constructional insert such as a door or a window frame (8) has a first web (20) which may have a self adhesive coating (18) for sticking the device to the frame and has a second web (22) which has a self adhesive coating (23) to which is stuck the membrane so that it can fall neatly into a cavity (6) between an outer wall (2) and inner wall (4) of the building without substantially bending the membrane. The webs of the device are preferably joined at right angles in a "T"-shape, the junction between the webs being preferably offset with respect to the centre line of one web. <IMAGE>

Description

DAMP PROOF MEMBRANE The present invention relates to a device for and method of securing a damp proof membrane in a building to a constructional insert such as a door or a window frame.

The current practice when building a door or window normally made of wood into exterior brick or blockworlc is to tack a damp proof polythene membrane onto the vertical sides of the insert frame and then bend the membrane out from the frame through 90 degrees. The membrane is then tucked into the cavity wall gap between the outer brickwork and the inner blockwork. Finally the wall cavity gap in the vicinity of the insert such as a door or window is filled and the inner blockwork and filling is plastered over.

A problem arises in this current practice in the region of the bottom of the vertical sides of the insert frame.

This is that it is hardly possible to fold or bend the membrane over neatly and drop this into the wall cavity gap. What normally happens is that the membrane is rucked up in the area adjacent to the vertical side and the brickwork in this area. Furthermore, the process of tacking the membrane to the frame is time consuming and of course each tack pierces the weatherproof priming of the woodwork.

Accordingly, a device for securing the damp proof membrane in a building to constructional inserts according to the invention comprises a longitudinal member having at least two webs, the one being at right angles to the other, at least one web having at least one of the outer surfaces of the web coated with a self-adhesive.

According to another aspect of the invention, a device according to the invention as defined above, is applied to at least one vertical side of a building insert and a damp proof membrane is applied to the adhesive coating so that the membrane can be located within a wall cavity gap.

The device for and method of securing a damp proof membrane according to the invention enables a membrane to be located within the wall cavity gap and secured in a damp proof manner to the insert frame without bending the membrane, the said or first adhesive coating being located in a plane substantially parallel to the median plane of the damp course gap.

Preferably both webs of the device according to the invention have adhesive coating so that one web can be simply stuck to the vertical side of the insert facing along a row of brickwork whilst the other web at right angles by means of its adhesive holds the membrane in a plane parallel to the line of brickwork. This preferred arrangement ensures that the device can be quickly and easily stuck to the insert frame and then the membrane stuck to the device. The device is preferably formed as a PVC extrusion in lengths of ~m or 3m which can be easily cut to size. In a preferred embodiment the webs of the device are so joined that the cross-section of the device is substantially T-shaped.The dimensions of the preferred embodiment are such that both webs are approximately 25mm wide by 1.5mm thick and the webs are joined at right angles so that the point of junction is approximately 6mm from one side of the web which is arranged to receive the membrane. The adhesive coating is preferably a self-adhesive covered by a covering strip which is removed before use.

An embodiment and a method according to the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a building wall with an insert, specifically a window, to which is adhered a device for securing a membrane according to the invention, and Figure 2 is a transverse cross-section of the device for securing a membrane shown in Figure 1.

In the drawings a building wall comprises an outer brickwork wall 2 and an inner blockwork wall 4 with a damp prevention cavity or gap 6 in between. On the top course of brick of wall 2 a window frame 8 is located.

The frame 8 has a vertical side 10 facing along the line of the wall 2, that is side 10 is located at right angles to the front facing 12 of the brickwork. A device 14 for securing a polythene membrane sheet 16 is secured to to side 10 bv means of an adhesive coating (see Fig. 2) 18 on a first web 20 of the device, whilst an adhesive coating 23 on a second web 22 of the device secures the membrane 16 so that it falls neatly into cavity 6.

The device 14 for securing the membrane comprises the two webs 20 and 22 formed as a single extrusion of PVC. Both webs are about 25mm wide and web 22 meets web 20 at right angles so that it overhangs about 6mm on one side of web 20 leaving about 17.5mm overhang on the other side, the thickness of the web being about 1.5mum. As supplied the device 14 is in lengths of 2 or 3m which are cut to the appropriate size. The adhesive coatings 18 and 23 are covered with protective backing 24.

In order to use the device 14, the length of the vertical side 10 is measured and a length of the extrusion 14 equivalent to the length of the side 10 with an extra DOmm or so is cut off from a standard length. From the cut off length 50mm of web 90 is cut off so that the remainder of web 20 is the length of side 10. The protective backing 24 is then removed from the adhesive coatings 18 and 23.

Web 20 is then stuck to frame side 10 by coating 18 with the lesser rear side 26 of web 22 abutted to the inner vertical side 28 of the frame 8. A portion 30 of the extrusion 14 is allowed to extend downwards against the inner face of brickwork 2. Membrane 16 is then inserted or may have already been inserted in cavity or gap t and positioned or cut so its vertical edge 32 aligns with edge 34 of web 22. membrane 16 is then stuck by adhesive coating 23 to extrusion 14.

Finally the cavity 6 15 filled at 36 and the inner ail 4 and filling 36 where it faces opening 38 is rendered and plastered.

It will be appreciated that the adhesion of the membrane onto web 22 of the extrusion or device 14 ensures the membrane does not have to be bent and no rucks occur.

The invention is easy and quick to use and carry Omit.

Claims

1. A device for securing a damp proof membrane in a building to a building insert such as a door or window frame member having at least two webs, the one being at right angles to the other, at least one of the webs having an outer surface coated with a self-adhesive.

2. A device as claimed in claim 1 wherein both webs have adhesive coating.

3. A device as claimed in claims 1 or 2 wherein the webs are so joined that the cross-section of the device is substantially T-shaped.

4. A device as claimed in any one of claims 1 to 3 wherein each web is approximately 25mm wide.

5. A device as claimed in claim 4 wherein the webs are approximately 1.5mm thick.

6. A device as claimed in claims 4 or 5 where the webs are joined at right angles so that the point of junction is offset approximately 6mm from one side of one said web.

7. A device as claimed in any one of claims 1 to 6 wherein the adhesive coating is covered by a covering strip which is removed before use.

8. A method of securing a damp proof membrane in a building to a building insert such as a door or window frame employing a device as claimed in any one of claims 1 to 7, applying the device to at least one side of the building insert, applying a damp proof membrane to the adhesive coating and locating the membrane within a wall cavity gap.

9. A method of securing a damp proof membrane as claimed in claim 8 wherein the cavity gap is filled at a position where the membrane is located in the gap the filline is then rendered and plastered where it faces the opening for the insert.

10. A device for securing a damp proof membrane in a building to a building insert such as a door or window frame substantially as described with reference to the accompanying drawings.

11. A method of securing a damp proof membrane in a building to a building insert such as a door or a window frame substantially as described with reference to the accompanying drawings.