Browse Forums Building Standards; Getting It Right! 1 Oct 15, 2010 8:30 am Can anyone provide advice in relation to rectifying an incorrectly installed Damp Proof Course. Indications are that Building Code requirements are that a DPC membrane should continue out to the external brick wall face. Our's does not, only reaching midway through the brick width, which means the first row of core holes within the brick are left unprotected. What options would be available to rectify this problem ...... would the existing brickwork need to be demolished? Looking forward to any advice. Re: Damp Proof Course Rectification 3Oct 15, 2010 8:13 pm B STAR where did you read this??? i wouldn't want the damp course coming out. Hi B Star Some info was obtained from Masonry Code AS3700 ... Clause 11.4.16 Further online research and earlier forum replies refer also to the The Building Code of Australia requirements for damp proof courses to be placed through the full thickness of the base of walls below floor level to form an impervious layer that keeps rising dampness out. Our previous homes have always had evidence of the DPC extending to the exterior wall .... another reason for our forum enquiry. Re: Damp Proof Course Rectification 4Oct 15, 2010 9:10 pm when i last read the BCA I am pretty sure it had to be 2/3 of the way for slab foundation. Perhaps is needs to be all the way if your building on stumps since you don't have any other barrier to prevent moisture coming up from the ground. Re: Damp Proof Course Rectification 6Jan 03, 2015 10:42 am If you bricks are from Boral, Austral or any of the other major masonry manufacturers then the following information is directly from ThinkBrick (which is the industry group which). Our bricks had to be torn down because our DPC was installed in a similar way to yours. Quote: From the ThinkBrick Guide to AS3700-2001: It is essential that the membrane DPC should be visible at the front surface of the wall after construction. This is best achieved by allowing the material to project while the masonry is under construction, followed by cutting it off flush or turning the edge down when construction is complete. The most common cause of dampness in masonry buildings is bridging of the DPC, either because of insufficient projection from the surface of the joint or by the application of a render coating after construction of the wall. Any external landscaping or rendering of the wall must not be allowed to bridge the DPC and form a path for moisture to pass above the DPC level. Where the wall is to be rendered to below the DPC, the DPC should not be cut off until after the rendering is complete. The most common reason for render failing is saline ground water wicking up through the render, drying and depositing salt, which builds up between the render and the brick, eventually popping the render off. The full document can be downloaded at... http://thinkbrick.com.au/system/uploads ... 1407727890 Australian Building Inspections Services explain on there website (at http://goo.gl/Uau3yH) that... Quote: The Building Code of Australia and Australian Standard AS3700 Masonry Code require dpcs to be placed through the full thickness of the base of walls below floor level to form an impervious layer that keeps rising dampness out of the interior of the house to prevent lifting of tiles, and deterioration of walling, furnishings and floor finishes. Where rising damp has caused mortar in external face brickwork to fret, the appearance of the brickwork can be restored by repointing the joints. Re: Damp Proof Course Rectification 7Jan 03, 2015 10:55 am 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp Proof Course Rectification 9Jan 03, 2015 8:03 pm Is rising damp really a problem in australia with the way we build. Remember we still have the moisture barrier wrap around the house. Originally wasnt the damp course simple for water behind bricks to escape out? Re: Damp Proof Course Rectification 10Jan 03, 2015 8:34 pm B STAR Is rising damp really a problem in australia with the way we build. Henley have an Alternative Solution certified by a qualified expert. Why not bring up that Alternative Solution and see what the certifying expert's justification for not following the BCA, the Australian Standards and the brick manufacturer's instructions is? 3in1 Supadiverta. Rainwater Harvesting Best Practice using syphonic drainage. Cleaner Neater Smarter Cheaper Supa Gutter Pumper. A low cost syphonic eaves gutter overflow solution. Re: Damp Proof Course Rectification 11Jan 03, 2015 9:06 pm SaveH2O B STAR Is rising damp really a problem in australia with the way we build. Henley have an Alternative Solution certified by a qualified expert. Why not bring up that Alternative Solution and see what the certifying expert's justification for not following the BCA, the Australian Standards and the brick manufacturer's instructions is? would be interesting to see. I have very porous bricks. Even though my damp course only comes out to 10mm from the edge it still stops the moisture from rising. So its still appears to be working. I can see it working very clearly. I will have to take note next time it rains heavily to see if the mortar is hydrophobic or not. It could be that the mortar has a high cement content and therefore not very porous. Re: Damp Proof Course Rectification 12Jan 03, 2015 9:48 pm Quote: Is rising damp really a problem in australia with the way we build. Remember we still have the moisture barrier wrap around the house. Originally wasnt the damp course simple for water behind bricks to escape out? Oh yes it is and has been since settlement. A correctly installed DPC to all walls and under slabs on ground will stop it in its tracks though ( if installed correctly ). The DPC behind a brick wall is a flashing to direct water to the outside of a building whereas the DPC at the bottom of a brick wall is to stop moisture rising from the ground. Stewie Re: Damp Proof Course Rectification 13Jan 04, 2015 7:42 am Just as important and harder to gauge is if the weep hole is blocked with mortar from the back. Cleaning it out after the wall is built is very difficult, remembering how hard it will be not to puncture the DPC Re: Damp Proof Course Rectification 14Jan 05, 2015 7:31 am I had a look at one of the weep holes on my home, and found the DPC to be set back about 1cm from the face of the brick. I'm guessing they did this to keep the appearance visually attractive. Considering it is a dry pressed brick with no holes, would thta 1 cm set back make any difference ? Re: Damp Proof Course Rectification 15Jan 05, 2015 11:27 am kavehman I had a look at one of the weep holes on my home, and found the DPC to be set back about 1cm from the face of the brick. I'm guessing they did this to keep the appearance visually attractive. Considering it is a dry pressed brick with no holes, would thta 1 cm set back make any difference ? Bricks are permeable and so the water can be absorbed by the bricks and move up the wall. Re: Damp Proof Course Rectification 17Jan 06, 2015 10:45 am I'd suggest that unless the ground and lower bricks are completely soaked that if the DPC is set back only 10mm you are still likely to get little or no moisture rising to the brickwork above the DPC. We used to get our brickies to set the DPC back about 6-8mm or whatever they were going to rake the mortar joints out. We never had a problem with rising damp on any of our jobs. Quote: whats the big issue if water rises though?? You have another moisture barrier between the brick and the house. So whats the actual risk if it does? The lower courses of the brickwork on a wall can absorb salts upwards from the ground leading to efflorescence and eventual decay of the bricks. Apart from looking unsightly, it can lead to the bricks themselves breaking down over a long period. Stewie Re: Damp Proof Course Rectification 19Jan 06, 2015 1:44 pm Stewie D I'd suggest that unless the ground and lower bricks are completely soaked that if the DPC is set back only 10mm you are still likely to get little or no moisture rising to the brickwork above the DPC. We used to get our brickies to set the DPC back about 6-8mm or whatever they were going to rake the mortar joints out. We never had a problem with rising damp on any of our jobs. Quote: whats the big issue if water rises though?? You have another moisture barrier between the brick and the house. So whats the actual risk if it does? The lower courses of the brickwork on a wall can absorb salts upwards from the ground leading to efflorescence and eventual decay of the bricks. Apart from looking unsightly, it can lead to the bricks themselves breaking down over a long period. Stewie I will agree with Stewie, a very competent answer. I can compliment that with some blogs on rising dampness: http://www.buildingexpert.net.au/blog/p ... -dampness/ http://www.buildingexpert.net.au/blog/r ... an-misery/ http://www.buildingexpert.net.au/blog/b ... e-eroding/ Foremost Building Expert in Australia,assisting with building problems/disputes, building stage inspections,pre-contract review advice for peace of mind 200 blogs http://www.buildingexpert.net.au/blog Have look at your house plans and you will probably find that brick articulation joint has been missed. Maximum allowable spacing is 6M or 5.5M for a wall with window… 17 20556 Hi all Am new to this forum. I want to get some ideas/info about how to manage an 80 year old factory restoration to convert to a residence. The factory floor is concrete… 0 6330 Unless the room is for storage then it's non compliant BCA V2 2019 S3 P3.8 You have 2 options 1. The builder deconstructs the section and rebuilds as per plan /… 7 10615 |