The North-Facing View on a Sloping Infill Plot
A client has agreed to buy a 0.18 ha infill plot on the edge of a village. The site has 18 m of frontage onto a public road on its southern boundary and falls about 2.5 m from the south-west corner to the north-east corner. A drainage ditch runs along the northern boundary, and a two-storey neighbour stands 4.0 m from the western boundary with habitable windows facing the plot. The client wants a two-storey house of about 180 m² with the main living spaces and a full-height glazed wall facing north to capture views of distant hills, a garage at the roadside, and a driveway entering at the north-western end of the frontage close to a bend in the road. The plot is zoned residential with a low-density objective. The client has asked you to confirm the design is ready to lodge and wants to start on site in eight weeks.
1. The client insists that the kitchen, dining and living areas all face north to take the view. Advise on this proposal, explaining the competing factors and how you would resolve them in the plan.
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The proposal is half right. North glazing gives even, glare-free daylight all day, which suits kitchens and screens, but in an Irish heating season it collects almost no useful solar gain. Heat demand here is driven by heat loss, and glazing loses heat roughly five to eight times faster than an insulated wall (about 1.0–1.4 W/m²K against 0.18–0.21 W/m²K). A 20 m² full-height north glazed wall would therefore add a permanent several-hundred-watt loss for no solar benefit, and would be the most expensive wall in the house.
Resolving view against orientation. Separate the two requirements: the view is a north-facing need, the heat is a south-facing one. Place the main living and dining space on the north-west corner so it holds the view through a controlled glazed area (roughly 25–30% of the wall, a wide low window rather than full height), and open a large south- or west-facing window or glazed door on the return wall for winter sun and evening light. Borrow south light into the north rooms over a half-height or single-storey element, and keep the plan depth to 10–12 m so daylight reaches the back of the rooms.
What goes north instead. Stairs, bathroom, utility, store and garage need little light: they should buffer the north elevation and reduce the glazed area.
Client expectation. State the trade-off explicitly and in writing: the north glazing will be designed and sized, not maximised. This avoids a redesign after the client sees the first drawings.
2. Identify the site and planning issues that must be resolved before a planning application is lodged, and explain how each could change the layout.
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Entrance sightlines. The proposed entry sits near a bend at the north-west end of the frontage. The roads section will look for visibility splays in both directions, commonly of the order of 70–90 m each way on a village road and considerably more on a faster road - always confirm the figure with the roads authority rather than assuming one. If the splay is obstructed by the boundary hedge or the bend, the entrance must move eastwards along the frontage, which in turn relocates the drive and garage.
Driveway gradient. The average fall is 2.5 m over roughly 40 m (about 1:16), but locally it will be steeper. Guidance typically wants the first 4.5–6 m from the road at no more than about 1:20, with a transition and a level platform at the garage. This fixes the garage floor level and may require cut and fill that affects the house level.
Surface water. Discharge to the public sewer is unlikely to be permitted. Percolation testing for a soakaway or an attenuation system is needed, and the northern ditch is a watercourse - discharging to it needs consent and may affect bank stability. This reserves land at the low, north-east corner.
Flood risk. The ditch creates a fluvial risk; a site-specific flood risk assessment may be required and finished floor level is normally set a minimum of 500 mm above the design flood level. This raises the house on the sloping site.
Overlooking. The neighbour is only 4.0 m from the western boundary with habitable windows facing the plot. Where opposing first-floor habitable windows fall within roughly 22 m, planners commonly seek obscure glazing, angled windows or a set-back - this constrains first-floor layout on the west side.
Services and boundary. Confirm water, power and broadband capacity, the right to maintain the ditch, and boundary treatment.
3. Describe the site layout drawing you would produce to support the application, and explain why each element is needed.
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Drawing format. A3 sheet at 1:200 (1:250 acceptable for the overall layout), with a north point, a graphic scale bar in metres, a title block naming the drawing, scale, date and revision, and a key. Levels in metres to two decimals, related to a stated datum.
What must appear, and the reason for each:
- Red line boundary and the public road with the centre line and edge of carriageway - establishes the site in relation to the public domain.
- Contours or spot levels at 0.5 m intervals across the whole plot, plus proposed finished floor levels for house and garage - this is the only way to demonstrate that the 2.5 m fall, the driveway gradient and the flood level can all be satisfied at once.
- Visibility splays hatched as two triangles from the entrance, with dimensions and the stopping distance quoted - the planner can check compliance without a site visit.
- Driveway centre-line with longitudinal gradients annotated along the run, and the transition point marked - proves the 1:20 requirement at the road is met.
- SUDS features (soakaway or attenuation area, swale) with dimensions and a note that percolation testing will follow.
- Building footprint, garage, private open space, bin and bike storage, landscaping and retained hedgerows.
- Overlooking analysis - window positions on the west elevation marked against the 22 m line to the neighbour.
- A cross-section A–A through the slope showing existing and proposed ground, cut and fill, and foundation depths.
Why it matters. The drawing is the argument: it should let the planner approve sightlines, levels and drainage without further information requests, which is what protects the eight-week programme.