Wednesday, June 15, 2016

Site Analysis for the New House Next to the Pond

In the first post about the NHND to the Pond, (read it HERE ) I mentioned how an architect-designed house such as this one starts with a site analysis and a program analysis.  Through the analysis of the site I review the legal, natural, man-made, and physical conditions of the specific building site, as well as the climate/solar path/prevailing winds. The "program" is the architect's term for the rooms or spaces needed/wanted (pretty standard in residential architecture) and where they should be placed in relationship to each other on the site.

Proposed Site Plan
First let's talk about legal restraints. These include required zoning regulations such as setbacks from property lines, water, etc. This information can help inform where the building or driveway/curb cut can be placed (without having to get a variance from the town or special permission from the DEC, for example). The zoning regulations will also set limits on the footprint size, maximum lot area to be covered, maximum and minimum building square footage, and maximum height of primary or accessory buildings so that something completely out of character with the neighborhood cannot be constructed without input/review. Some laws can also include "pattern" books or suggested materials or styles- this is mostly found in village centers and historic districts, and not relevant for this project, which is located outside the village boundary on a rural road.

Open Meadow by the Road
The natural features of the site were then examined. This site is large with a stream, pond, wetlands, rock outcroppings, wooded and meadow areas.  There is a lot of grade change and a surveyor was engaged to create a topography map so we could read how water drains off the hillside. This map helps the designers figure out where the rock outcroppings are and where the land/soils might be most suitable for the house, the well, and the septic (SDS) system.

The man-made features on the site include a old farm path leading up the hill, a rudimentary stream crossing (which did not meet current standards and needed to be upgraded), meandering old stone walls at some property lines, and utility poles along the edge of the road. These features are all shown on the survey as well. In a neighborhood or a smaller site, neighboring buildings would be taken into consideration, so the placement of the new building fits in (see NHND post showing a site plan in a village HERE ) but on this site, we have no "context" like that that we need to be sympathetic to.

The physical conditions, like soil type, were looked at by the engineer to determine the design of the SDS system. He also determined the volume of water (design is always for the worst case - the 100 year flood) that will be coming down that hillside so as to design proper drainage for the driveway, and around the structures. This helps set the finish floor elevation and the garage slab elevation so that the building is up enough to be dry, without having its foundation sticking out too much. It also helps us figure out the grading into the garage for a car and setting that so that we don't need an excessive amount of steps between garage and house.
Correctly designed overhangs let in winter sun and block summer sun

 One of the most important things I look at during the site analysis is the solar orientation. Following the track of the sun across the sky helps layout what rooms might go where and informs the orientation of the long axis of the building. When at all possible, it's best to have the long axis north-south with an eave overhang for shading in summer. Creating a diagram of the height of the sun in winter (when we want to let the sun it the house) and summer (when we want to shade the house from the sun) informs the size of the roof overhangs.

Site Analysis informs design of house
So the site analysis of this pond property showed that what at first glance looked like the best building spot - the level meadow by the road- was not legally allowed, as it was within the DEC wetlands buffer. Therefore, a long driveway would have to be constructed up the hill to a building site in the woods. We elected to have the driveway come from the road at the southern edge of the property, even though this meant crossing the stream, because it meant not crossing through this wetlands buffer, which a driveway from the northern edge would have to do. (the engineer stated that steam crossing would be the easier permit to get). And this way we could re-use the existing farm lane as our driveway, therefore requiring less clearing and re-grading than a new driveway from the north edge of the property.

The SDS system and it's expansion area were placed where the soils could handle the percolation required. The house site was decided to be on a level-ish area not-too-far up the hill in the woods with the house oriented such that it's long axis faces south for ideal solar advantage. A walk-out basement recreation room could be incorporated in the northwest corner where the grade slopes down toward the pond. The garage could be tucked behind on the north, not blocking light or the view of the beautiful house as one approaches. (us architects always want to hide the cars/garage) The south/front of the house can have the porch my clients want while also functioning as the entry, and the west side- near the pond- can be the place for the screened porch. Now we are starting to get into program analysis - and that can be the next post.