GB2385880A

GB2385880A - Method of treating building masonry

Info

Publication number: GB2385880A
Application number: GB0300465A
Authority: GB
Inventors: David Craick Moore
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-03-01
Filing date: 2003-01-09
Publication date: 2003-09-03
Anticipated expiration: 2023-01-09
Also published as: GB2385880B; GB0204795D0; GB0300465D0

Abstract

A method of treating building masonry includes the use of a solid rod (1) of a substance, or a porous tube (2) filled with a substance, which reacts with water to treat the building masonry. The substance may be injection powder which comprises, in parts by weight:- <SL> <LI>a) 40 parts ordinary Portland cement, <LI>b) 8 parts silica sand, <LI>c) 1 part tartaric acid, and <LI>d) 8 parts soda ash. </SL>

Description

A METHOD OF TREATING BUILDING MASONRY Field of the Invention This invention relates to a method of treating building masonry, e. g. brickwork, blocks, stones and the like, to combat and/or eliminate rising damp.

Various methods are currently employed to combat problems relating to rising damp and consequent decay in buildings. Such methods range from injecting remedial liquids, gels, slurries and pastes, to the insertion of electrodes to conduct water-repelling electrical charges. All these methods require special tools, which are expensive. Some methods also require a continuous electrical supply. In addition, some of the chemicals which are used contain inflammable solvents, are irritant or leave stains on masonry. Some of the chemicals are also malodorous and/or unpleasant to handle. Some methods rely on filling holes with frozen liquids or creams, which may flow away into cavities.

A well-established existing method of inhibiting rising damp, which requires less equipment and is more stable in situ, involves drilling 21 mm. diameter holes into the mortar between adjacent courses of bricks at 110 mm. centres. The drilled holes are then filled with a substance known as"injection mortar", which sets hard in the drilled holes and, over a period of time, diffuses crystals into the mortar. The crystals and mortar form a matrix which is impervious to damp. The "injection mortar" is prepared by mixing a quantity of "injection powder" with water, and the prepared"injection mortar"is then placed in a gun similar to that used for injecting mastic into cracks and injected into the holes.

Although widely used, this method has five main disadvantages, as follows :- 1) it requires an expensive gun, 2) the prepared"injection mortar"has a very short usable life of about thirty minutes, during which time the mixture can become very hot, with the result that the mixture can solidify in the gun and hence become unusable, 3) the"injection mortar"powder is highly alkaline and hazardous to skin and lungs during mixing, 4) the"injection mortar"powder has to be mixed with a precise proportion of water immediately prior to its use, and 5) large diameter holes are required, which is destructive to masonry, particularly to brickwork.

A more recently introduced method substitutes an"injection cream"for the injection powder, but suffers from similar

disadvantages in that it requires the use of a special gun, is unpleasant to handle if spilt on the skin, and needs to be injected via a tube. Its use also produces additional problems, associated with a mobile"cream", which can contaminate surrounding materials and leave a repellent stain. In addition, the"cream"is supplied in a foil container which has to be removed from the gun after use and requires safe disposal.

It is accordingly an object of the present invention to provide an improved method of treating building masonry to combat rising damp.

Summary of the Invention According to a first aspect of the present invention there is provided a method of treating building masonry which includes the use of a solid rod of a substance, or a porous tube filled with a substance, which reacts with water to treat the building masonry.

The solid rod or porous tube is preferably dry and rigid for ease of handling.

The substance is preferably injection powder and may be pre-reacted with water to form the solid rod. The injection powder may, alternatively, be unreacted and contained inside the porous tube. The unreacted powder may also be contained within a porous sack contained within the porous tube.

The porous tube may have removable end caps.

The injection powder may comprise, in parts by weight :- a) 40 parts ordinary Portland cement, b) 8 parts silica sand, c) 1 part tartaric acid, and d) 8 parts soda ash.

In carrying out the invention, holes drilled into the masonry may be wetted using a hand spray, hose-pipe or watering can and then the rods or tubes simply and permanently inserted in the holes. The rods or tubes may be driven into the holes, particularly if they are a tight fit, using a dowel or the like. Several rods or tubes may be inserted into a single drilled hole, one after the other, depending on the thickness of the wall being treated.

As opposed to wetting the holes, the rods or tubes of the substance may be pre-wetted, for example, by placing them in a bucket of water for a predetermined length of time and then inserting them in the drilled holes in the building material to be treated.

As a further alternative, which is appropriate for the treatment of severe cases of rising damp, the rods or tubes of the substance are simply inserted in the drilled holes in the building material to be treated and the substance reacts with the water present in the building material.

Another possible procedure again involves inserting the rods or tubes of the substance in the drilled holes in the building material to be treated, followed by injection of a measured quantity of water into the substance using a syringe.

A further alternative procedure, which involves the use of tubes containing the substances, includes placing a tube in a drilled hole and then withdrawing the tube itself while leaving the substance in position within the hole, the tube being withdrawn over a spigot which serves to retain the substance in the hole. This procedure is particularly useful when the substance is held in a porous sack within the tube and is pre-wetted.

According to a second aspect of the present invention there is provided means for treating building masonry comprising a plurality of solid rods of a substance, or a plurality of porous tubes filled with a substance, which reacts with water to treat the building masonry, and a wetting tray having a plurality of recesses which, in use, are filled with water prior to placing the rods or tubes in the recesses.

Brief Description of the Drawings Figure 1 is a perspective view of a rod, Figure 2 is a perspective view of a tube, and

Figure 3 is a perspective view of a wetting tray.

Description of the Preferred Embodiments The solid rod 1 shown in Figure 1 is formed from injection powder, pre-reacted with water, and typically has a diameter within the range of from 10 to 25 mm. and a length of from 75 to 100 mm. The rod 1 can be of round or oval cross-section, or of any other cross-section such as square, and can be serrated at one end (as shown) to facilitate fitting thereof in a drilled hole.

The injection material from which the rod 1 is produced typically has a composition, in parts by weight, as follows :- a) 40 parts ordinary Portland cement, b) 8 parts silica sand, c) 1 part tartaric acid, and d) 8 parts soda ash.

Pre-reaction of the dry powder with water is effected by adding 6 parts by weight water to 10 parts by weight of the dry mixture.

In carrying out a treatment operation, holes are drilled in the building material which is to be treated and then, depending on the thickness of the wall and the depths of the drilled holes, one or more of the rods 1 is inserted in each drilled hole.

The tube 2 shown in Figure 2 comprises a layer of a porous material such as that sold under the designation"VYON HP".

"VYON"is a registered trade mark of Porvair pic of Kings Lynn, Norfolk. The porous material is typically of 3.2 mm. thickness and the tube 2 is typically 20 mm. in diameter and 75 mm. in length.

Smaller diameter tubes may also be used. The ends of the tube 2 are closed by non-porous end caps 3 and 4.

Tubes 2 of this size are suitable for use in the damp-proofing of the skin of a cavity wall and are filled with a dry injection powder having the following proportions in parts by weight :- a) 40 parts ordinary Portland cement, b) 8 parts silica sand, c) 1 part tartaric acid, and d) 8 parts soda ash.

To treat the skin of the cavity wall, holes of from 10 to 21 mm. diameter and of 75 mm. depth are drilled at 100 mm. centres into the mortar between adjacent courses of bricks. Effective "salting"of the brickwork can thus be obtained by drilling relatively small diameter holes.

A wetting tray 5 (see Figure 3) is provided and is provided with a series of recesses in the form of channels of such size that the tubes 2 can be fitted in the channels, as shown in Figure 3.

The channels of the wetting tray 5 are filled with water and the tubes 2 are placed in the channels and allowed to stay in the channels for ten minutes while they absorb the water in the

channels. The tubes 2 are then removed from the channels in the wetting tray 5 and inserted in the drilled holes. The injection mortar sets in the drilled holes and produces the required chemicals which diffuse outwardly through the porous material into the surrounding masonry to form the damp-proof course.

It is to be appreciated that the specific examples described above in relation to the drawings are given for a better understanding of the invention and that the rods and tubes may be of varying compositions and sizes and used in a variety of ways.

A preferred method of making the rods 1 comprises extruding the injection powder, after pre-reaction of the dried powder with a metered quantity of water, followed by forced drying of the solid rod.

Claims

Claims :-

1. A method of treating building masonry which includes the use of a solid rod of a substance, or a porous tube filled with a substance, which reacts with water to treat the building masonry.

2. A method as claimed in Claim 1, in which the solid rod or porous tube is dry and rigid for ease of handling.

3. A method as claimed in Claim 1, in which the substance is injection powder and is pre-reacted with water to form the solid rod.

4. A method as claimed in Claim 1, in which the substance is injection powder and is unreacted and contained inside the porous tube.

5. A method as claimed in Claim 1, in which the substance is unreacted powder which is contained within a porous sack contained within the porous tube.

6. A method as claimed in Claim 4 or Claim 5, in which the porous tube has removable end caps.

7. A method as claimed in Claim 1, in which the substance is injection powder which comprises, in parts by weight :- a) 40 parts ordinary Portland cement, b) 8 parts silica sand,

c) 1 part tartaric acid, and d) 8 parts soda ash.

8. A method as claimed in any one of the preceding claims, in which holes drilled into the masonry are wetted using a hand spray, hose-pipe or watering can and then the rods or tubes simply and permanently inserted in the holes.

9. A method as claimed in Claim 8, in which several rods or tubes are inserted into a single drilled hole, one after the other, depending on the thickness of the wall being treated.

10. A method as claimed in any one of Claims 1 to 7, in which, the rods or tubes of the substance are pre-wetted, for example, by placing them in a bucket of water for a predetermined length of time and then inserting them in the drilled holes in the building material to be treated.

11. A method as claimed in any one of Claims 1 to 7, in which the rods or tubes of the substance are simply inserted in the drilled holes in the building material to be treated and the substance reacts with the water present in the building material.

12. A method as claimed in any one of Claims 1 to 7, which involves inserting the rods or tubes of the substance in the drilled holes in the building material to be treated, followed by injection of a measured quantity of water into the substance using a syringe.

13. A method as claimed in any one of Claims 1 to 7, which includes placing a tube in a drilled hole and then withdrawing the tube itself while leaving the substance in position within the hole, the tube being withdrawn over a spigot which serves to retain the substance in the hole.

14. A method of treating building masonry substantially as hereinbefore described with reference to the accompanying drawings.

15. Means for treating building masonry comprising a plurality of solid rods of a substance, or a plurality of porous tubes filled with a substance, which reacts with water to treat the building masonry, and a wetting tray having a plurality of recesses which, in use, are filled with water prior to placing the rods or tubes in the recesses.