TWO STOREY  NZEB  EXTENSION  TO TWO STOREY SEMI- DETACHED HOUSE IN LAYTOWN CO.MEATH

Floor Area– Existing House 80 sq.m  + Proposed Extension 120sq.m

Brief

Open plan kitchen/dining /family room, light filled & spacious, energy efficient, low maintenance, unique contemporary style, privacy, functional space.

Planning

Pre -Planning.

Design Concept

Minimum intervention to original 1950s house , demolition of 1970s rear single storey extension ,maximize solar gain , use building mass of new ground floor  open plan extension  to hug the external boundaries , and create a private courtyard garden . Clerestorey glazing  located to provide privacy to boundaries in addition to evening sun , combined with Storey height glazing to courtyard to give illusion of more space.

Flat roof with anthracite Sika trocal finish  and Triple Glazed ‘ monitor style’ roof lights ,a restricted palette of natural high quality materials -Silicone white render wall finish to existing house, quartz sandstone to ground floor extension , & boundary walls , Fibre cement rainscreen cladding to first floor extension ,  ,storey height  & clerestorey TB  Aluminium TG windows, , granite paving , composite soffit boarding  &  screen cladding.

Construction Method

Ex House – External insulation system ( ETICS ) combined with insulation upgrades to roof & new concrete ground floor. Thermal break aluminium TG replacement windows.

Ground floor – Quartz sandstone  wall cladding  to solid concrete block pumped cavity wall , combined with Thermal lite blocks at critical junctions to reduce Linear Thermal Bridging ( LTB ) , steel frame structure with metal deck & in situ  concrete flat roof to ground floor extension  , airtightness membranes & taping in conjunction with  airtight plaster finish internally to external walls, triple glazed  thermally broken aluminium clerestorey windows , sliding doors /screens & rooflights .

First floor – Insulated Timber frame structure , externally finished in rainscreen cladding , & trocal flat roof finish .

Renewables

Air to water electric heat pump for space & water heating used in conjunction with UFH

PV with battery storage

MVHR or DCV ventilation with heat recovery.

100% Low energy lighting ( LED ).

Energy Rating

Preliminary BER B2 – To comply with TGD –L Nzeb  ( upgraded from G )

Airtightness target – Q50 <2.5m3/h/m2 to comply with TGD –F

Status

Feasibility Stage  – awaiting Budget costing to decide if  economically viable.