WO1988008905A1

WO1988008905A1 - Ventilation means

Info

Publication number: WO1988008905A1
Application number: PCT/DK1988/000077
Authority: WO
Inventors: Flemming Dalum-Larsen
Original assignee: Dalum Larsen Flemming
Priority date: 1987-05-08
Filing date: 1988-05-09
Publication date: 1988-11-17
Also published as: DK184188D0; DK161846B; DK184188A; DK161846C

Abstract

A ventilation means (1) for building in into a facing wall is described. The ventilation means is in the form of a box-shaped structure having a top wall (2), a bottom wall (3), two opposite side walls (4, 5), a substantially open front wall (6), and a substantially open rear wall (7). The cross-section defined by the top, bottom and side walls (2, 3, 4, 5) is restricted by a screen (8), and the width (b) of the ventilation means corresponds to the width of a joint in the facing wall. The screen is adapted to prevent the invasion of mason bees etc., but to allow the necessary passage of air.

Description

Title: Ventilation means

This invention relates to a ventilation means for building in into a construction made from building blocks for ventilation of a cavity behind it. More particularly, the invention relates to a ventilation means for building in into a facing wall for replacenment of the previously used open vertical joints for ventilation of the cavity behind it.

Continued demands for reducing the energy expenditure in connection with the heating of houses have increased the necessity of tightening and insulating houses. At the same time the importance of securing an adequate ventilation of the very building construction has become more and more obvious. In recent time the importance of an efficient pressure equalization has also increasingly been brought into focus.

A generally used building construction comprises a bearing construction of concrete slabs or a wooden frame construction which after insulation with mineral wool is coated with a facing wall of bricks or the like on its exterior side. In order to secure adequate ventilation of the mineral woolfilled cavity some of the vertical joints are left open, in an ordinary single- family house usually each third vertical joint in the third course.

In practice, however, the open vertical joints have turned out to result in certain problems, since it will be possible for insects such as mason bees, wasps, etc. to invade the wall construction through the open vertical joints and build their nests in places difficult of access. These places may furthermore be difficult to locate making it almost impossible to get rid of the insects. It stands to reason that such a constantly increasing swarm of mason bees in the immediate vincinity of the house may be very disturbing.

This problem has now been solved by the present invention, which provides a ventilation means for building in into a construction made from building blocks for ventilation of a cavity behind it, said ventilation means being characterized in, that it is in the form of a substantially box-shaped structure having a generally closed top wall, a generally closed bottom wall, two opposite, generally closed side walls, a substantially open front wall and a substantially open rear wall, that the cross section defined by said top, bottom and side walls is restricted by a screen member, and that the width of the ventilation means substantially corresponds to the width of a joint between the building blocks.

The screen member used is adapted to prevent the passage of insects such as mason bees, wasps, etc., but still allow the necessary passage of air.

As the width of the ventilation means substantially corresponds to the width of a joint between the building blocks, the ventilation means may be inserted to replace some of the joint sections when building a construction made from building blocks. For reasons of strength the ventilation means will usually be placed in a vertical joint, and accordingly, the present invention is explained on the basis thereof. If, however, conditions of strength allow the ventilation means to be placed in a horizontal joint, this will obviously also be possible. In a preferred embodiment the height of the ventilation means corresponds substantially to the height of a building block, allowing the ventilation means to be inserted in the construction in an aesthetically pleasing fashion. In another preferred embodiment, which is particularly suited for building in into the lowest course, the height of the ventilation means corresponds substantially to the height of a building block plus the width of a joint. Such ventilation means may be placed directly on the foundation to secure a good drainage of any water collecting at the bottom of the cavity and the insulation. Appropriately, the depth of the ventilation means substantially corresponds to the depth of a building block, as this partly secures that the air passage is not impeded by mortar, and partly secures that the ventilation means does not project too far into the construction.

In a currently preferred embodiment the screen member is located at the rear wall of the ventilation means, so that the screen is not visible from the outside when the ventilation means has been built in into a wall. If, however, it is desired to utilize the decorative effect of the screen member it may obviously also be located at the front wall of the ventilation means, just as the desired effect to keep out insects such as mason bees, wasps, etc. may obviously also be achieved by any intermediate location of the screen member.

In order to facilitate the drainage of any penetrating driving rain it is preferred in those cases where the ventilation means is to be inserted at a higher level in the construction that the bottom wall of the ventilation means be raised at the end being closest to the rear wall whereby an acute angle with the horizontal is formed. The sloping bottom wall may either be established by inserting an additional wall or by lowering the bottom wall between the side walls to form a recess on the outer side of the ventilation means. In both cases there is achieved the additional effect of strengthening the ventilation means in a lateral direction. In the latter case the recess also allows a better anchoring of the ventilation means in the mortar.

In general, the acute angle will be in the range from 0° to 10°, preferably from 1° to 5°, and especially preferred from 1° til 3°, but other angles may be used, provided that they result in a sufficient open area to secure the desired ventilation.

In order to facilitate working with the ventilation means it is preferably symmetrical about a horizontal plane thebeby making it unneccesary to take into account, which end has to turn upwards and which end has to turn downwards. In those cases where the bottom wall is raised at the end being closest to the rear wall, this means that the top wall is lowered in a similar manner at the end being closest to the rear wall. When placing the ventilation means it is then sufficient to ascertain once and for all to which side the screen member has to turn in order to assure that the bottom wall is sloping outwards, whereafter the other ventilation means merely are to be placed with the screen turning in the same direction.

However, it may also be desired to form the ventilation means in such a way that it is not symmetrical about a horizontal plane. For instance, a ventilation means for building in into the lowest course in such a way that the ventilation means rests directly on the foundation, may be shaped with the corner formed by the front wall, the rear wall and the side walls cut off. For instance, the incision may be shaped in such a way, that a rectangular portion of the lower front corner of each side wall and the portion of the bottom wall lying between these parts is missing, but other embodiments, for instance with a more rounded outline, are also conceivable. In a direction perpendicular to the bottom wall, the incision has a depth corresponding substantially to the width of a joint, e.g. from about 5 to about 20 mm, preferably from about 10 to about 15 mm. In a direction perpendicular to the front wall the incision usually has a depth which allows scraping out of the joint prior to after-pointing. According to the Danish Standard, "Dansk Hurvεrksnorm DS 414", all horizontal joints are to be scraped out to a depth of 13 mm and after-pointed. Accordingly, the incision will appropriately have af depth of about 15 mm or more in a direction perpendicular to the front wall, but other depths will be conceivable, depending on the local regulations, e.g. depths from about 5 to about 25 mm, preferably from about 10 to about 20 mm and especially about 15 inn. In this embodiment the ventilation means will usually be of a height substantially corresponding to the height of a building block plus the width of a joint. It has turned out that a ventilation means of this structure may be used advantageously at a higher level in the construction, e.g. below parapets and the like. In this case the ventilation means is placed with the incision turning upwards and outwards in such a way that the bottom of the ventilation means is in line with the bottom of the adjacent building blocks. The incision has the effect that an uninterrupted horizontal joint may be established above the adjacent building blocks in such a way, that the ventilation means optically merges with the construction. At the same time, the joint pointed in the incision will function as a drip for driving rain. A further improvement in the drainage of driving rain may be achieved if the top wall of the . ventilation means, which in this particular position functions as bottom wall, is lowered inwards at the rear wall of the ventilation means, so that it will slope outwards in this position.

Accordingly, in a preferred embodiment of the present invention the ventilation means is provided with an incision at the corner formed by the front wall, the bottom wall and the side walls, and the top wall is lowered at the end being closest to the rear wall. This results in a construction which, depending on which way it turns, provides special advantages at different places in a building construction. In the above, the ventilation means has been described in connection with building in into a new construction; but obviously the ventilation means will also be applicable for building in into existing open vertical joints to solve problems in connection with insects. In this application it may be advantageous to use a ventilation means having a reinforced front edge, as it will be more able to resist the impact of being driven into the joint, and it may also be advantageous it the ventilation means is provided with at least one protuding stop member at the front wall, whereby the ventilation means may simply be driven into the wall until the stop member makes contact with the surrounding wall or joint. For instance, the stop member may be in the form of a collar or a pair of tabs protuding at the front wall as an elongation of same, and with a width not exceeding the width of a joint, so that they may be brought to make contact with the joint when driving in the ventilation means and optically merge therewith.

The ventilation means according to the invention is preferably made of a plastic material such as polyvinylchloride, polypropylene or polyethylene, said materials being easy to form into the desired shape and easy to colour in shades corresponding to the generally used mortar colours. For instance, the production may be carried out by injection moulding making it possible to make the ventilation means in one piece.

The ventilation means may also be made of other materials, e.g. galvanized iron, powder-cast metal such as silu ine or other metals. If desired, there may also be used a combination of different materials, e.g. the screen member may be made of wire mesh, whereas the remainder of the ventilation means may be made of a plastic material.

The invention is further illustrated in the following with reference to the drawings, wherein Figure 1 is a schematic view of a facing wall with ventilation means according to the invention inserted; Figure 2 shows a simple embodiment of the ventilation means according to the invention; Figure 3 shows a modification of the embodiment shown in figure 2 which is especially suited for insertion into an existing open vertical joint; Figure 4 shows another embodiment of the ventilation means according to the invention; and Figure 5 shows a third embodiment of the ventilation means according to the invention.

Figure 1 is a schematic drawing of a facing wall under construction with ventilation means 1 according to the invention inserted between each third brick in the third course. The other joints are filled with mortar in the usual fashion. Figure 2 shows a simple embodiment of a ventilation means 1 according to the invention. The ventilation means is made by injection moulding of a plastic material, e.g. polyvinylchloride coloured in an appropriate grey shade, which corresponds to the colour of a mortar joint. The ventilation means is in the form of a box-shaped structure with a substantially open front wall 6 and a substantially open rear wall 7, a closed top wall 2, a closed bottom wall 3 and two opposite closed side walls 4, 5. Parts of top wall 2 and side wall 5 are removed to show how the cross section defined by top, bottom and side walls 2, 3, 4, 5 is restricted by a screen member 8 at the rear wall 7 of the ventilation means. The screen member 8 is made integrally with the remainder of the ventilation means and is formed with openings of a size preventing the passage of mason bees, etc., but allowing the necessary passage of air. The width b of the ventilation means corresponds to the width of a joint between the building blocks used, e.g. between the bricks used in the facing wall of figure 1, whereas the height and the depth of the ventilation means corresponds to the height and depth, respectively, of a building block. Figure 3 shows a modification of the ventilation means of figure 2 which is particularly suited for insertion into an open vertical joint in an existing construction. The front edge of the ventilation meanS_j is reinforced enabling the ventilation means to better resist the driving in into the joint, and the front wall 6 is provided with two protruding stop members 9, the width of which does not exceed the width of a joint, so that they may be brought to make contact with the joint when the ventilation means is driven into the wall, and optically merge therewith.

Figure 4 shows another embodiment of the ventilation means according to the invention. Parts of the side wall 5 have been removed to show how the bottom wall 3 is raised at the end being closest to the rear wall 7 thereby forming an acute angle v-with the horizontal, as indicated by the dashed line. Also in this case the screen member 8 is located at the rear wall 7 of the ventilation means. When building-in such ventilation means it must be ensured that the ventilation means is turned in such a way that bottom wall 3 slopes in the direction of the exterior side of the construction in order to drain away any penetrating driving rain from the construction. The elevated bottom wall 3 forms together with the side walls 4, 5 a recess on the outer side of the ventilation means, which results in a better anchoring of the ventilation means in the mortar layer.

If it is desired to avoid the inconvenience of constantly having to take care that the ventilation means shown in figure 4 is turned in such a way that the bottom wall slopes towards the outer side of the construction, the ventilation means may be formed to be symmetrical about a horizontal plane, viz. the top wall 2 is lowered at the end closest to the rear wall 7 in the same manner as the bottom wall 3 is raised, so that it will be of no importance which side is turned upwards and which side is turned downwards.

Figure 5 shows a currently preferred embodiment of the ventilation means according to the invention. As indicated the ventilation means is provided with an incision at the corner formed by the front wall 6, the bottom wall 3 and the side walls 4, 5. The depth d, of the incision in a direction perpendicular to the bottom wall 3 corresponds substantially to the width of a horizontal joint, whereas the depth d₂ of the incision in a direction perpendicular to the front wall 6 is such that it allows scraping out of the joint prior to after-pointing. The height h of the ventilation means corresponds substantially to the height of a building block plus the width of a joint. As in figure 4 the screen member is at the rear wall of the ventilation means.

In the above the ventilation means according to the invention has been described, exemplified by some specific embodiments. However, it should be appreciated that various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims

PATENT CLAIMS

1. A ventilation means (1) for building in into a construction made from building blocks for ventilation of a cavity behind it, CHARACTERIZED in that said ventilation means is in the form of a substantially box-shaped structure having a generally closed top wall (2), a generally closed bottom wall (3), two opposite, generally closed side walls (4, 5), a substantially open front wall (6} and a substantially open rear wall (7), that the cross-section defined by said top, bottom and side walls (2, 3, 4, 5) is restricted by a screen member (8) and that the width (6) of the ventilation means substantially corresponds to the width of a joint between the building blocks.

2. A ventilation means according to claim 1, CHARACTERIZED in that the height (h) of said ventilation means substantially corresponds to the height of a building block plus the width of a joint.

3. A ventilation means according to claims 1 or 2, CHARACTERIZED in that said ventilation means is provided with an incision at the corner formed by the front wall (6), the bottom wall (3) and the side walls (4, 5).

4. A ventilation means according to claim 3, CHARACTERIZED in that the incision has a depth (d,) in a direction perpendicular to the bottom wall (3) which substantially corresponds to the width of a joint.

5. A ventilation means according to claims 3 or 4, CHARACTERIZED in that the incision has a depth (d₂) in a direction perpendicular to the front wall (6) which allows scraping out of the joint and after- pointing.

6. A ventilation means according to any of the preceding claims, CHARACTERIZED in that the screen member (8) is located at the rear wall (7) of the ventilation means.

7. A ventilation means according to any of the preceding claims, CHARACTERIZED in that the top wall (2) is lowered at the end being closest to the rear wall (7) and/or the bottom wall (3) is raised at the end being closest to the rear wall thereby forming an acute angle (v) with the horizontal.

8. A ventilation means according to claim 7, CHARACTERIZED in that the lowered top wall (2) and/or the raised bottom wall (3) together with the side walls (4, 5) form a recess on the outer side of the ventilation means.

9. A ventilation means according to any of the preceding claims, CHARACTERIZED in that the front wall (6) of said ventilation means is provided with at least one protruding stop member (9).

10. A ventilation means according to any of the preceding claims, CHARACTERIZED in that it is made in one piece.