First floor roof garden and terrace:
1. Mr McDonald found the whole (60sqm) of the membrane had failed based on his investigation of only 0.8% of the area. There was no evidence of any further investigation by Mr McDonald as to whether the remaining 99.2% of the membrane was defective. There was uncontested objective evidence to the contrary namely the invasive examination undertaken by Mr Haramis which revealed the limited area of blistering which diminished quickly to nil at 500mm from the western hob and the membrane was fully bonded. In respect of the upturn there was no objective evidence to support the assertion of Mr McDonald that the upturn height was insufficient. The builder submits the objective evidence was that the height of the upturn on the upper floor was between 150mm to 170mm and that an upturn of 150mm was appropriate; and
2. After the builder had left the site, the homeowners installed a rooftop garden, including an irrigation system, to a height of 180mm according to Mr McDonald or higher but without an edge restraint, a gravel drain, edge protection of the upturn and protection of the drainage outlets, thereby allowing water from the garden to go over and behind the membrane upturn causing the blistering observed by Mr McDonald. Mr McDonald failed to undertake any water tests of the membrane on the first floor to test the validity of his conclusions that the membrane had failed.
- The builder further submits that the findings of the Tribunal in relation to the membrane were also against the weight of the evidence of the water proofer, Mr Haramis. The builder submits that the Tribunal has made an error in disregarding the evidence of Mr Haramis: see par 56 of the Liability Decision. In that paragraph the Tribunal stated that it had disregarded the opinion evidence in pars 67, 68 and 69 of Mr Haramis' affidavit relating to the waterproofing installation. The builder submits that those paragraphs do not give opinion evidence, rather, those paragraphs give evidence only of fact.
- The builder submits that the evidence of Mr Haramis was to the following effect:
1. The membrane in the area exposed by Mr McDonald did not peel away as claimed by Mr McDonald and to obtain a test square of membrane he had to cut it out with a knife and use a knife to lift it off the concrete slab. Mrs Babeck was present and saw that; and
2. There was no evidence to suggest that the remaining membrane was not still intact.
- The evidence of Mr Haramis is that he found in relation to the waterproofing membrane to the ground floor balcony that:
1. The membrane sample he obtained was more than the minimum required thickness;
2. The top surface of the tiling was slightly above the top of the waterproofing upturn in the open drain running across the front of the balcony for its entire length; and
3. The moisture level on top of the hob in that area was 59.5%
- Similarly the evidence of Mr Haramis is that he found in relation to waterproofing to the first floor terrace that:
1. In the limit exposed area the membrane was blistering at the cross over of the waterproofing upturn and the render;
2. Blistering diminished quickly to nil at 500mm from the western hob;
3. The membrane was fully bonded when tested by others, presumably Mr McDonald.
- The builder made further submissions concerning the evidence under cross examination of Mr Haramis and submits that Mr Haramis was an experienced and licensed water proofer who undertook the work in a proper and workman like manner.
- The builder refers to the conclusion of the Tribunal, based upon the evidence of Mr McDonald that the widespread failure of the waterproofing membrane meant that removal and replacement of all waterproofing membrane was required. The builder submits that that finding was against the weight of evidence, that patching is common practice in the construction industry and that patching of membrane is used in the construction process as part of staged completion of liquid membrane applications. Mr McDonald acknowledged that patching may be undertaken in the circumstances he identified and whether patching is appropriate depends on a number of factors.
- The builder refers to the assertion by Mr McDonald that a patch repair would not have been able to achieve a bond between old and new membrane and submits that that is based upon a reference which has nothing to do with adhesion between old and new membrane.