Tuesday, September 28, 2010

Buffer - Open Space Types















Buffer

The buffer has the basic elements of a green, with the added purpose of buffering the impact of traffic from a highway or boulevard. Shown is a small lot development fronting a green. On the opposite side are larger lots on which houses are placed further back from the roadway edge as another buffer technique.

Copyright (C) 2000
Architectural GRAPHIC Standards CD-ROM
John Wiley & Sons, Inc. New York, NY

Thursday, September 9, 2010

Soil Horizons

Horizon, soil is a layer of soil, approximately parallel to the surface, having distinct characteristics produced by soil-forming processes. In the identification of soil horizons, an uppercase letter represents the major horizons. Numbers or lowercase letters that follow represent subdivisions of the major horizons. The major horizons are as follows:

O horizon. An organic layer of fresh and decaying plant residue.
A horizon. The mineral horizon at or near the surface in which an accumulation of humified organic matter is mixed with the mineral material. Also, any plowed or disturbed surface layer.

E horizon. The mineral horizon in which the main feature is loss of silicate clay, iron, aluminum, or some combination of these.

B horizon. The mineral horizon below an O, A, or E horizon. The B horizon is in part a layer of transition from the overlying horizon to the underlying C horizon. The B horizon also has distinctive characteristics, such as (1) accumulation of clay, sesquioxides, humus, or a combination of these; (2) granular, prismatic, or blocky structure; (3) redder or browner colors than those in the A horizon; or (4) a combination of these.

C horizon. The mineral horizon or layer, excluding indurated bedrock, that is little affected by soil-forming processes and does not have the properties typical of the overlying horizon. The material of a C horizon may be either like or unlike that in which the solum formed. If the material is known to differ from that in the solum, an Arabic numeral, commonly a 2, precedes the letter C.

R layer. Hard, consolidated bedrock beneath the soil. The bedrock commonly underlies a C horizon but can be directly below an A or a B horizon.

Wednesday, August 25, 2010

Landscape Goals

The urban landscape is a set of interdependent elements that creates a
controlled sense of place. It includes thoroughfare type, building type,
frontage type, and the form and disposition of landscape.

Public landscaping plays many roles above and beyond that of ornamentation:

1. To correct inadequacies of spatial definition caused by building frontages.
Planting steady rows of trees at the edges usually reduces the
height-to-width ratio of the street space. Grids of trees are used to fill
gaps left by unbuilt lots and surface parking.

2. To adjust the microclimate by providing the appropriate level of shade or sun
for buildings and sidewalks. For thoroughfares running east-west, this may
involve the use of asymmetrical planting.

3. To support the intended urban or rural character of the public space.
Selecting appropriate species and varying the species planted, as well as the
regularity of their disposition, can alter the landscape significantly.

4. To create a pleasing visual composition, being careful to mask the aesthetic
failure of certain buildings as well as to reveal the successes. Consider
seasonal changes of each species.

5. To create a harmonious whole of specific character by coordinating public and
private plantings. Selection should vary, to ensure resistance to pests, but
not result in an incoherent collection of specimens. Native species should
predominate to reduce maintenance, with an emphasis on species that support
wildlife compatible with human settlement.

Copyright (C) 2000
Architectural GRAPHIC Standards CD-ROM
John Wiley & Sons, Inc. New York, NY

Tuesday, August 24, 2010

Basic Techniques for Radon-Resistant New Construction


1. Gravel: Use a 4-inch layer of clean, coarse gravel below the “slab,” also called the foundation. This layer of gravel allows the soil gases -- including radon -- that occur naturally in the soil to move freely underneath the house. Builders call this the “air flow layer” or “gas permeable layer” because the loose gravel allows the gases to circulate.

NOTE: In some regions of the country, gravel may be too expensive or unnecessary. Alternatives are allowed, such as a perforated pipe or a collection mat.

2. Plastic Sheeting or Vapor Retarder: Place heavy duty plastic sheeting (6 mil. polyethylene) or a vapor retarder on top of the gravel to prevent the soil gases from entering the house. The sheeting also keeps the concrete from clogging the gravel layer when the slab is poured.

3. A Vent Pipe: Run a 3-inch or 4-inch solid PVC Schedule 40 pipe, like the ones commonly used for plumbing, vertically from the gravel layer (stubbed up when the slab is poured) through the house’s conditioned space and roof to safely vent radon and other soil gases outside above the house. (Although serving a different purpose, this vent pipe is similar to the drain waste vent -- DWV -- installed by the plumber.) This pipe should be labeled "Radon System." Your plumber or a certified radon professional can do this

4. Sealing and Caulking: Seal all openings, cracks, and crevices in the concrete foundation floor (including the slab perimeter crack) and walls with polyurethane caulk to prevent radon and other soil gases from entering the home.

5. Junction Box: Install an electrical junction box (outlet) in the attic for use with a vent fan, should, after testing for radon, a more robust system be needed.

from: http://www.epa.gov/radon/rrnc/basic_techniques_builder.html

Saturday, August 21, 2010

Frontage Types - Shopfront













Shopfront

The facade is aligned directly on the frontage line, with the entrance at grade.
This type is conventional for sidewalk retail. It is often equipped with an awning or a porch. A transition line should separate the signage from the facade
above. The absence of a setback and elevation from the sidewalk prevents residential use on the ground floor, although it is appropriate above.

Copyright (C) 2000
Architectural GRAPHIC Standards CD-ROM
John Wiley & Sons, Inc. New York, NY

Friday, August 20, 2010

Frontage Types - Front Lawn










Front Lawn

The facade is set back substantially from the frontage line. The front lawn this creates should be unfenced and visually continuous with adjacent yards. The ideal is to simulate buildings sitting in a rural landscape. A front porch is usually not appropriate, since no social interaction with the street is possible at such a distance. The large setback can provide a buffer from heavy traffic, so this type is sometimes found on boulevards.

Copyright (C) 2000
Architectural GRAPHIC Standards CD-ROM
John Wiley & Sons, Inc. New York, NY

Thursday, August 19, 2010

Frontage Types - Porch & Fence












Porch and Fence

With an encroaching habitable porch, the facade is set back substantially from the frontage line. The porch should be within a conversational distance of the sidewalk. A fence at the frontage line marks the boundary of the yard.

Copyright (C) 2000
Architectural GRAPHIC Standards CD-ROM
John Wiley & Sons, Inc. New York, NY