This is best method statement for installation of Exterior Insulation Finishing System also called EIFS. Following materials shall be used for the typical installations.
TERRACO STYROFIX: Styrofix is an adhesive for the TERRACO Exterior Insulating Finishing System (EIFS). It is easy to use by just adding /mixing with water, improving on-site quality control. It shows excellent adhesion between substrate and EPS (Expanded Polystyrene) insulation boards.
TERRACO STYROBOND: Styrobond DP is a basecoat and adhesive for the TERRACO Exterior insulating finishing system. It is easy to use by just adding /mixing with water, improving on-site quality control. It shows excellent adhesion between substrate and expanded polystyrene boards when used as an adhesive. It also provides an excellent basecoat for embedding glass fibre mesh on top of which EIFS finishing coat is applied.
TERRACO TERRAMESH: Terramesh is a standard mesh that is inter woven, open-weave, twisted strands for compatibility with TERRACO Styrofix & TERRACO Styrobond DP. It is alkali resistant and weighs approximately 160gm/m2. The fiberglass mesh maintains tensile strength and flexibility for long term durability
TERRACO TEXTURED PRIMER: Textured Primer is an acrylic based pigmented primer in liquid form, which is partially absorbed into the substrate of cementitious materials, plasters and limes. It binds the substrate and the surface, to give a solid base for decorative finishing coats, such as TERRACO TEXTURED COATINGS.
TERRACO PENETRATING PRIMER: Penetrating Primer is a highly developed product in liquid form, which is absorbed deeply into the substrate of cementitious materials, plasters and limes. It binds the substrate and the surface, to give a solid base for decorative finishing coats, such as TERRACO Textured Coatings, paints and thin-layer mortars. Penetrating Primer is supplied in two forms, white and clear.
TERRACO TEXTURED COATING: Terracoat Textured Coating is a range of ready-mixed acrylic textured coatings. It provides the unique combination of a quality architectural finish with outstanding economy through ease of application, a low material consumption rate and surface durability. Terracoat is guaranteed for 10 years against de-bonding and cracking. Terracoat adheres to most exterior and interior surfaces including plywood, chipboard, anti- rust primed steel, gypsum dry wall, sand/cement render and concrete. Terracoat has been developed to withstand extreme climatic conditions such as desert climate and extreme cold. Terracoat Excel and Terracoat Granule are the products of choice for finishing the Terraco EIFS system.
Detailed Construction Sequence (Methodology)
TERRACO EIFS can be defined as an energy efficient thermal wrapping applied to the exterior surfaces of a building finished with a long-life, decorative and protective coating system. The use of TERRACO EIFS can substantially reduce heating or cooling costs and also allows for the use of lower specification cooling systems. As TERRACO EIFS is an energy efficient system, it consequently helps reduce green- house gas emissions.
Area of Use
TERRACO EIFS can be used on both old and new constructions. As it is applied as an exterior system, it is highly suitable for upgrading older buildings to reduce operating costs while giving a new attractive finish
1 – SURFACE PREPARATION
The surface should be clean, dry and sound, following to be considered for preparation of surface for EIFS application.
Damp: Rectify causes and allow drying out.
Dusty / Dirty: Brush down, steam clean and prime with TERRACO PENETRATING PRIMER.
High porosity: Seal the substrate by applying TERRACO TERRABOND A (diluted 1:3 with water).
Efflorescence: Brush down and prime with TERRACO SILPRIME.
Algae / Mould: Clean, sterilize with TERRACO Sterilizing Solution and prime with TERRACO PENETRATING PRIMER.
Mortar Lumps: Remove mechanically.
Grease, shutter oil remains: Steam clean, using detergent additives. Wash off again with water.
Render with damaged areas: Remove loose render; fill holes and repair the surface where required with TERRACO TERRAMIX REPAIR MORTAR.
Chalky Coatings: Brush down, clean and prime with TERRACO PENETRATING PRIMER.
Peeling Coatings: Remove old coating, steam clean and prime with TERRACO PENETRATING PRIMER.
2 – BEARING PROFILE INSTALLATION
2.1. Bearing component for EIFS is constructed of Aluminium.
2.2. Fix bearing profiles at 50cm intervals at least 25cm above ground level. The bearing profile should be fixed above DPC level. Use appropriate spacers to adjust level of base profiles.
2.3. The width of the bearing components should correspond to the width of the EPS insulation Board specified for the specific area on the project.
3 – FIXING INSULATION BOARDS
3.1. Recommended dimension of the Insulation board: 0.6m x 1.2m (density recommendation: between 15 – 24 kg/m3as per project specification/requirement). Thickness of the insulation board should be as specified for specific area on the project. The EPS/ Graphite enhanced EPS insulation boards should be fire retardant, CFC free and comply with ASTM C578 -10.
3.2. For level & even substrate: Apply 1 coat of TERRACO STYROFIX adhesive over the entire insulation board surface using a notched trowel.
3.2.1. For uneven substrates, with up to 20mm variation in level, apply TERRACO STYROFIX adhesive using spot /dab method covering 40% of the board.
3.2.2. For variations above 20mm, chipping of substrate or fixing higher thickness insulation board is advisable
3.3. Insulation board edges should be kept adhesive free to prevent thermal bridging.
3.4. Fix insulation boards in staggered pattern and ensure all outside and inside corners are interlocked, offset insulation board’s joints 200mm or more from the corners of openings around doors, windows or other similar conditions. Ensure that window corners are cut from one piece of board. Insulation boards must not bridge expansion joints in masonry or concrete substrates. Install a movement/expansion bead if such joints present.
3.5. Affix insulation board to the substrate ensuring it is level (use plumb line / spirit level).
3.6. Back wrapping with reinforcing fibreglass mesh and embedding mortar (TERRACO STYROBOND DP) is recommended for all insulation boards edges at system terminations (ends / openings) to reinforce the edges and also prevent water ingress.
3.7. Allow to dry for 24 hours.
4.1. Mechanical Fasteners are fixed directly through the uncoated board after a minimum of 24 hours.
4.2. Fasteners should penetrate minimum 4 cm into concrete substrates and minimum 7cm into the AAC/ ALC substrates to secure anchorage. Ensure dowel heads are sunk into the insulation boards to prevent bumps in the final finish.
4.3. We recommend a minimum of 4 Fasteners at the corners & 1 fastener in the centre of each board (for board of size 0.6m x1.2m).
4.4. Fasteners should be preferably made of plastic to avoid thermal bridging.
4.5. All dowel heads & gaps must be patched over using TERRACO STYROBOND DP and left to dry before base coat is applied.
5.0. CORNER PROFILES, FIBERGLASS MESH AND BASE COAT APPLICATION
5.1. For corners, window lintels and columns use PVC corner profiles with 8 – 12cm fiberglass mesh to give straight edges. Fix window reveal beads as required.
Important: It is essential to use beading to avoid cracks and leakage around windows and doors. TERRACO TERRACRYL sealant can be used in conjunction with beading as a flexible gap filler and sealant. Use of an appropriate window sill is recommended
5.2. Apply 1 coat of TERRACO STYROBOND DP by hand or spray to an approximate thickness of 2mm and immediately embed the (145 – 160g/m²) glass fiber mesh (Terramesh) into the surface by trowelling from the centre out to avoid any wrinkles. A minimum thickness of 1.5mm (2.5kg/m²) should be achieved.
5.3. Overlap all fiber glass mesh [TERRAMESH] edges by 10cm. Allow the first layer of TERRACO STYROBOND DP, 12 – 16 hours drying time before applying the second layer.
Contact Zone: For areas up to 3 m height from ground level, apply 2nd coat of TERRACO STYROBOND DP at 1.5 to 2mm thickness and embed second layer of Terramesh into the surface by trowelling from the center out to avoid any wrinkles. Allow this layer of TERRACO STYROBOND DP to dry for 12 – 16 hours before applying subsequent layer.
5.4. Apply another coat of TERRACO STYROBOND DP @ 1 to 1.5 mm thickness and level off. Total thickness of basecoat is 3 -3.5 mm for non-contact zones and 4.5 to 5.5 mm for contact zones.
Note: It is important to prevent water ingress behind the EIF system. Therefore special care should be taken to treat all gaps between system & walls especially above window & door heads, beneath window & door sills, sides of windows & doors, at roof /wall intersections, abutments of lower walls with higher walls, projecting features & base of the walls etc. Fill in the gaps with PU foam, cut back and seal with appropriate exterior grade sealant e.g. TERRACO TERRACRYL. A better option would be to fix suitable aluminium flashing over these gaps to direct water to the exterior. The top of the wall should be covered with suitable aluminium copping. Gaps around flashings should be sealed with TERRACO TERRACRYL. Gaps between aluminium base profile & walls should also be sealed.
6.0. DECORATIVE FINISH
6.1. Allow the last layer of the TERRACO STYROBOND DP to cure for 72 hours. In conditions of high temperature and low humidity or when windy, it may be necessary to keep the surface moist by mist spraying water to facilitate curing.
6.2. Apply 1 coat of TERRACO TERRABOND A (diluted 1:5 with water) and allow to dry.
6.3. Apply 1 coat of TERRACO TEX PRIMER (color to match TERRACO TERRACOAT EXCEL or TERRACO TERRACOAT GRANULE) and allow to dry.
6.4. Apply 1 coat of TERRACO TERRACOAT EXCEL or TERRACO TERRACOAT GRANULE by trowel to a thickness of 1.5 – 2mm with a material consumption rate of 2.5 – 3kg m² and allow to dry.