DOORS AND WINDOWS (top)
	Door and window frames and timber surrounds should always be removed to enable Platon membrane to be extended around or into door and window reveals to maintain the continuity of the waterproofing system and to also provide a physical barrier between the frames and damp masonry. In situations where the Platon membrane would restrict or limit the profile of replaced frames, then Platon wall/floor junction or Platon dpc plain can be used to line and protect the reveals instead.

 

	VENTILATION (top)
	There is no requirement to ventilate the membrane cavity in a fully sealed system such as in under pavement vault application. In a Semi sealed system, the cavity between membrane and substrate can be vented into the room space with passive vents or if this is not possible, it can be vented through the external wall using an 150 x 225 air brick inserted ever 1.5m to 2.0m along the wall. It is important that the cavity between the membrane and internal finish i.e. dry lining is not vented so as to avoid possible interstitial condensation. However, consideration should be given to the risk of condensation forming within the room itself and the introduction of a humidistat controlled extract fan should therefore be recommended.

 

	WALL FINISHING (top)
	If timber battens are to be used, the traditional method is to fix a vertical batten 25mm x 50mm. The brick plugs in this instance should be fixed at 400mm centres horizontally and 600mm centres vertically. The timber batten is screw fixed into to the self-tapping hole, which has been formed in the Platon brick plug using a size (10) x 2" screw. NB we would however, recommend that foil back plasterboard be used to prevent interstitial condensation forming in the cavity.
	For a metal fast track dry lining system such as Gypliner or Lafarge, the brick plugs should be fixed at 600mm centres horizontally and 800mm centres vertically. If an independent timber or metal frame system is to be used, the wall membrane can be 'curtain hung'. The membrane is simply dressed down the walls just like hanging a curtain or sheet. This method of installation requires less fixings. NB we would however, recommend that foil back plasterboard be used to prevent interstitial condensation forming in the cavity.
	On fair faced walls the Platon plaster dab collar system can be used. The collars, which incorporate a built in fixing plug going through the centre of the collar, are sealed as before with rope on the collar face rather than under the fixing plug head. The fixing collars are set out according to the width of the plasterboard to be used. (See fig 44 & 45)
	Generally, eight collars per sheet of plasterboard are required. The dab collars on the edge will also take the next sheet of plasterboard. When the collars have been fixed, insert 25mm size 10 screws into the pre-formed hole of the brick plug and adjust the screws in or out as the case may be to a constant final fix level for the final board finish.
	Mix the plasterboard adhesive in accordance with manufacturers instructions, and apply dabs of adhesive to the collars, ensuring that it goes through the collar gridding, and generously covers the levelling screw heads. Place some batten off cuts on the ground under the bottom of the plasterboard to support it until the adhesive has set. Stand the plasterboard on these support battens; position and press home onto the adhesive until the levelling screws stop any further movement.
	The plasterboard must now be left for the adhesive to set, after which the support battens can be removed. NB unfortunately, this form of dry lining system cannot be used with foil back plasterboard because the adhesive won’t adhere to the foil back material.
	If an independent brick/block wall needs to be built in front of the Platon wall membrane and requires lateral restraints, then ‘Isola bluebird fixings’ can be used or a similar suitable product. The ‘Isola bluebird fixings’ fixing is screwed into the self-tapping hole of the Platon brick plug and is anchored into the mortar bed joint as the wall is built. Independent free standing walls can also be built directly off Platon floor membranes, but we would recommend advice is sought from our technical department before proceeding.

 

	FLOOR FINISHES (top)
	There is a wide choice of floor coverings that can be laid on top of the Platon floor membrane. Listed below are some of the common applications.
-	Platon Multi & P5 (Wood Based Flooring) – Flooring grade T&G chipboard, Parquet, laminate, and wood strip.
-	Platon Multi & P5 (Sand & Cement Screeds) Domestic - min 50mm screed or 20mm reinforced polymer modified self-levelling screed. Industrial – min 75mm reinforced screed or 35mm reinforced polymer modified self-levelling screed.
-	Platon P20 (Wood Based Flooring) - Flooring grade T&G chipboard. Parquet, laminate, or wood strip can also be applied, but a T&G chipboard base should be laid first.
-	Platon P20 (Sand & Cement Screeds) - Domestic - min 75mm reinforced screed. Industrial – min 100mm reinforced concrete.

 

	INSULATION (top)
	For Platon membrane applied to walls at or above ground level, the maximum insulation thickness should be 50mm. When Platon membrane is applied to earth retaining walls full height of a basement, there is no upper limit to insulation thickness. However, if Platon membrane is applied to part earth retaining walls, then the maximum insulation thickness should be 50mm. There is no upper limit to insulation thickness for Platon membrane applied to solid floors at ground or below ground level.

 

	CURVED SOFFITS AND VAULTED ROOMS (top)
	When working in a conventional vault with rounded ceilings the water can run off freely and the following method should be adopted: -
	When lining vaults always work from the front to the back, starting on the centre line of the vault. Measure the length of the vault and add 400mm to this measurement, then cut the membrane to the length. Form a 900 downturn crease 200mm in from either end of the membrane and prepare the Platon brick plugs by wrapping with Platon sealing rope as previously described.
	Offer the membrane up to the vault ceiling along the centre line of the vault, and drill and hammer home the fixing plugs in a straight line at 600 centres from front to rear. These will provide fixing points for the dry lining system. The creased downturn at either end of the vault will start to deform going into the curvature of the vault ceiling. Where this occurs, carefully slit/cut the deformed sections, towards the crease but stop short of the crease by one stud.
	The membrane can now be overlaid and will flatten out and follow the curvature. Several slits may be required to achieve this depending on the radius of the vault. Continue to work out from the first sheet, ensuring a weathered joint of not less than eight studs. The flange should be used to make both of these weathered joints either side of the initial membrane fixed off the central line of the vault. The weathered joints are sealed flange over stud using Platon sealing tape in the manner previously described earlier.
	All the sheets running from front to back of the vault are cut overall length of vaulted soffit. This should give coverage to the vault, past the springing line down to the floor slab line, together with a 200mm return to either end of the vault.
	The end walls are now ready to be lined with the membrane. The end wall sections are cut to the true width of the vault so that the membrane overlaps the membrane returns already formed. These sections of membrane are fixed and sealed in exactly the same way as described for wall application. The end wall membrane stud to stud joint should be sealed around the radius with Platon sealing rope and if necessary corner strip. The floor membrane is now ready to be laid over the completed drainage system. The wall/floor junction, corner strip or creased upstand is always in front of the wall membrane and sealed on the perimeter with Platon sealing tape or rope as the case may be.

 

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