On the Roof Construction of Membrane Waterproof
Author: Yang Fan
Translator：Zhou Youqun
Abstract: This paper tries to solve the problem of roof waterproof at present though making a general study on the construction of the widely-used membrane waterproof.
Keywords: roof; waterproof membrane; construction
Roofing project housing construction is an important project, which has a bearing on the quality of life of the building. Will directly affect people's production activities and normal life. According to statistics, leading to roof leakage due to a few areas: materials accounted for 20% ~ 22%, accounting for 18% Design ~ 26%. Construction accounted for 45% ~ 48%, manage and maintain accounting for 6% ~ 15%. Currently roofing many new materials, but still waterproof layers of membrane where they have an important position, This paper focus on the roofing membrane waterproof construction.
1 Waterproof roofing membranes to do pre-construction work following
(1)pre-construction work of the technical preparations
Roof construction, the construction units should organize technology management personnel examined roof engineering drawings, master construction plan in detail the structure and the technical requirements for the project and in accordance with the actual situation in the preparation of the roof construction project or program technical measures. This left to avoid construction defects, resulting in reworking, while construction works based on organization and planning work started, preventing omissions, confusion, reversed affect the quality of the projects.
With construction organization, the next person to the construction team responsible for technical clarification. Include: construction sites, the construction sequence, construction technology, construction level, node security methods, location and practices, Quality standards to ensure the quality of technical measures, refined measures of protection and safety precautions.
(2)of the construction personnel and construction procedural requirements
The waterproof roof must be professional teams or waterproof construction workers, prohibited without qualification certificates units and non-professional teams or non-waterproof waterproof the roof for the waterproof construction, building units or management companies should seriously check on the construction of appointment cards. Construction of the construction units should construction processes, the level of quality of self-inspection and self-inspection, correcting them and do construction records, supervision units do every step of the inspection process, only after inspection and acceptance process for the next Road, the level of operations.
(3)the waterproof material quality requirements
Roofing projects using waterproof materials should document the quality of materials and quality inspection by the designated department’s certification; ensure their quality meet the "Roof Engineering Technical Specification" (GB50207-94) or the relevant state standards. Waterproof materials enter the scene should be accompanied by single factory inspection reports and factory certification, and indicate the date of production and batch number, specifications, names. Construction units should be required to review the sampling, sample review in strict accordance with the kind sent to witness the sampling system representatives of the construction unit or units to witness the Commissioner, under construction at the scene samples were sent to laboratories for experiments. After passing the review, the author reviews the test report before the single pass in waterproof engineering application. Prohibiting the use of substandard engineering waterproof material, substandard materials found to be an immediate withdrawal of all construction sites.
2 Roofing construction points.
(1)Construction of environmental requirements
To ensure that the construction and operation of membrane know the quality, to the +50 C to +350 C temperatures under construction; polymer modified asphalt and polymer membrane is not the negative temperature following construction hot-melt Stones roll in-Maastricht above the temperature conditions under construction, this membrane low temperature, and negative temperature, not Frost. Rain, snow, frost, fog, or atmospheric humidity is too large, and very windy weather is not appropriate for open operations, otherwise, we should take corresponding measures.
(2) of the slope roof drainage requirements
Flat Roof drainage slope of 2% - 3%, when the slope of less than 2%, the selection of material to find slope; When the slope is greater than 3%, it should use the structure for Singapore. Gutter, canopies longitudinal groove slope of not less than 1%, ditch drop shall not exceed 200 mm. looking for the bones around the mouth diameter of 500 mm within the slope of not less than 5%.
(3) the roof grassroots gap cracks treatment
The grassroots are precuts concrete panels, boards and panels between the slot width is less than 20 mm, using fine aggregate concrete pouring spaced, stone size may not exceed 10 mm, the intensity level not less than C20, and the possible expansion of the use of cement or doped expanders for mixing the concrete irrigation seam; When the plate between the plate and the slot width greater than 40 mm, joints should be in place within a ф6 reinforced by design or configuration of steel, pouring concrete joints End, timely coverage and water conservation seven days, the strength of the concrete must meet the C15, can continue its construction. Concrete irrigation slit prevent premature to bear loads of construction to ensure that partitioned the paste strength.
The grassroots are precuts concrete panels, boards and panels between the slot width is less than 20 mm, using fine aggregate concrete pouring spaced, stone size may not exceed 10 mm, the intensity level not less than C20, and the possible expansion of the use of cement or doped expanders for mixing the concrete irrigation seam; When the plate between the plate and the slot width greater than 40 mm, joints should be in place within a ф6 reinforced by design or configuration of steel, pouring concrete joints End, timely coverage and water conservation seven days, the strength of the concrete must meet the C15, can continue its construction. Concrete irrigation slit prevent premature to bear loads of construction to ensure that partitioned the paste strength.
(4) Leveling layer of roofing requirements
Know leveling layer is waterproof layers of membrane at the grassroots level to provide a waterproof membrane formation, density, strength, bonding structure basis. Therefore, the Stones roll leveling layer should be solid, not a prominent corner and pockmarks or surface with sand, when using 2-meter-long ruler inspection, the ruler and leveling the surface of the gap should not exceed 5 mm. the gap only allows changes gently, and with each meter length not more than one. Leveling the surface layer consisting of the adjacent corner should create an arc or obtuse angle.
When the grass-roots level to the overall concrete, cement mortar leveling layer thickness of 20 mm mortar and cement ratio of 1 : 2.5 ~ 1:3 (volume ratio), cement grade of not less than 42.5. Leveling layer should also set up separate compartments joints and filling them with sealing material, it would avoid or reduce the leveling layer cracking, even when the temperature structural deformation or deformation, waterproof layer will be formed cracks, resulting in leakage caused. Elastically to 20 mm, the separate compartments seam vertical and horizontal distance of not more than 6 m, separate compartments joints located at the roof slab-supported, Roof waterproofing layer corners, and prominent members of the roof's edge, waterproof layer and the parapet's edge, and so on. And with the slit-plate alignment, uniformity straight. Mortar leveling layer construction, the first floor roof and clean up the debris sprinkler humid. Laying the mortar, according to the last by far, is in the process, and every minute inside a continuous paved, Design Control by good slope, with 2 m length scratching posts particles when mortar slightly after the resumption of water, with Mazi compaction disappearing, 12 hours after the coverage with straw bags and water conservation. For highlights on the roof of the structure and other details of pipeline root node should do arcs, and cone-cone or Taiwan side, A small stone and concrete made to avoid nodes Stones roll fracture site, which will help real fast sticky.
1.Looking for the bones mouth: around 500 mm within causing steep ≥ 5%, and smoothing.
2.Parapet, roofing stack up, the staircase layer of the root cause arc radius of 80 mm, small stone with concrete made.
3.Roof pipeline extending around the roots, using fine aggregate concrete cone caused Taiwan side, conical bottom width of 300 mm, 60 mm high, Leveling TROWELING.
(5) Primary treatment agent
To strengthen the grassroots and waterproofing membrane between the bonds, guarantee integrity, in the pre-construction waterproofing layer, Brushing advance of the primary coating. Common primary treatment agent is a weak cold with a variety of oil and polymer modified bitumen membrane and synthetic polymer membrane supporting the end of the plastic (primary treatment agent), and the membrane should choose the material compatibility, in order to avoid being corrupted or membrane incompatible bond from the bad.
Cold weak oil, primary treatment agent spraying, Tu test prior to leveling layer of dry and cleaned up, Then brush on the roof of nodes, peripheral, such as parts of the corner first, the last large area to spray, brush. Spraying, to thin brush uniform, we can not leak or too thick white skin. Cold weak oil in a former brick-two days of brushing, brushing primary treatment agent after four days before drying Stones roll.
(6) The Stones roll
1. Know the direction of the roll. Coil direction of the roll-out should be under roof slope and roof has to determine the vibration. When the roof slope is less than 3%, parallel to the membrane to the roof brick; Roof slope of the 3% ~ 15%, Coil can be parallel or perpendicular to the roof brick; Roof slope is greater than 15% or vibration, Asphalt should be perpendicular to the membrane roof brick, the other based on the actual situation can consider using parallel or vertical brick roof. From the roof eaves to the laying of a layer by layer, from top to bottom should all roll lap, multi-layered membrane lap position should be staggered upper and lower vertical membrane not Know.
2. Coil affixed in the order. Waterproof layer construction, should make nodes, additional layer of roof drainage and more concentrated location (such as roofing and water subsides connectors, eaves, Gutter, canopies groove, we turned the corner and roofing, slab joints, etc.) and then from the lowest elevation Roofing Construction Department upward. Installing Gutter, canopies ditch membrane; it should ditch Sunchon, eaves direction and reduce overlap. Know more inter-and multi-level roof, it should first high to low since the first term of the order.
3. Coil lap method and width. Stones roll used lap, on the lower deck and two adjacent membrane lap joints should be staggered. Parallel to the seam roof of the structures should flow smoothly lap direction: perpendicular to the roof of the structures should shun local joints with the dominant wind direction lap. Lying of the layers laminated membrane, the Gutter and roofing link should adopt cross-access law lap, tie should stagger the joints; joints in the roof to stay Gutter or indirectly, should not stay in the ditch.
Slope exceeds 25% of arched roof and skylights under the slope, we should try to avoid short side lap, lap short side, in the lap should take to prevent the membrane slide measures.
(7) Waterproofing membrane detail approach
Flashing and roofing intersection of the grassroots should be made obtuse angle (“1350) or circular (R = 50 ~ 100mm). waterproof layer to the vertical wall on the high volumes not less than 250 mm, 300 mm often; membrane should heal Connection with Yan, Department mouths shut to prevent water seepage, the waterproofing membrane eaves into free fall in, the outside eaves, walls daughter Gutter several forms.
(8) The roofing membrane protection
Waterproofing membrane Stones completed, the need for protection, so as not to affect the waterproof effect. Waterproof level capped at 300 mm x 300mm expanded perlite insulation blocks, In its further above additional 3 cm thick layer of cement mortar protective layer, the layer of steel wire cloth, protective layer established separate compartments spaced, seam sealing material used for filling, better protection of waterproof layer.
3 Precautions
To block from the steam room, caused the emergence of roofing Bulge, Standing on the general structure of the roof to take the insulating layer install exhaust Road and made its isolation air layer (such as waxed one, or a blanket 2 oil, or a plastic cloth 2), block infiltration of water vapor upward. Road to exhaust distance of 6 meters vertical setup, not plugged, and the atmosphere connected with the exhaust vent connected, drainage layer of roofing construction, we should check whether the exhaust Road has been blocked, and be clean, and clear.
4 Conclusions
Roofing membrane waterproofing layer is not a very difficult thing, as long as we follow the waterproof roof membrane processes construction, layers implement strictly controlled and standardized according to seriously carry out every step, we can stop the construction of roof leakage.
