Landscape Designer

[The Hornings]

Badly in need of designer to help with decking design, front porch, and
landscaping. Living in a remote area in Midwest and have no one available to
help...

Is there any service such as this online? I have a roof problem (ice freeze
up/dams) and need a designer to figure out how to design a porch to aliviate
this problem

thanks..

[Ralph Hertle]

The Hornings:

In Michigan it is common for the eaves of a house to be roofed not with shingles
but with aluminum sheet metal. Above the eaves there are shingles. The ice and
snow slide off the metal. Since the shingled roof above the eaves is warmer the
snow melts earlier creating a water flow over the eaves. If the snow on the
colder eaves does not melt or slide off the water is trapped above. The water
then backs up and infiltrates beneath the shingles above the eaves causing
leaking and insulation failure. The metal roofing on the eaves can also be
applied as a retrofit for an existing roof.

Deep flashing is always a good precaution. Depending on the slope, extend the
metal, bonded with flashing adhesive, up to a vertical height of more than 12"
beneath the shingles. Water drainage and ventilation provision is also important
beneath the roofing and from under the siding.

A complete new roof made of standing seam sheet steel or aluminum will, of
course, permit the ice and snow to slide off. That's good. Use horizontal snow
holder rods over the house entrances to prevent occasional slides and danger to
people from the ice and snow. The problems there are that a rather dynamic
somewhat industrial appearance is created, and, also, that the plastic finishes,
e.g., Kynar, while durable, reflect the sun for 100 miles. That's a problem in
the far West where peaceful vistas are often interrupted with scores of glaring
roof tops from great distances away.

The idea of a roofing system is that the uppermost barrier deflects the rain,
ice, and snow. For example, like a tiled roof. Below that, the roof is
relatively dry, and the evaporated water from the space between the roofing
membrane or tiling above and the insulation below will be drained and vented
away, keeping the insulation dry.

On the interior of the shell an impermeable sealed membrane vapor barrier, e.g.,
of polyethylene or aluminum foil laminates, should be placed inside of the
insulation, and usually under the interior gypsum wall board. No air or vapor
transmission is acceptable from the interior, especially in the North. In the
South, e.g., Houston, where heavy air conditioning is the ordinary you may want
the vapor barrier on the outside of the insulation where the primary
condensation takes place. The moisture in the interior (or exterior in the
South) will condense on the vapor barrier and not within the insulation, thus
preventing the degradation of the efficiency of the insulation.

Standing snow on the roof is not a problem if the eaves don't block the runoff,
and there is ample dry insulation.

The most general ideas? An outer barrier to the elements. No standing water or
leakage. Vent the insulation. Keep the insulation dry via a vapor barrier on the
warm side of the insulation. Use deep aluminum flashing and flashing cement at
fasteners, and use extra flashing at wall and roof penetrations.

Stop air infiltration through the house walls to prevent hot air loss. Tyvek
spun bonded fabric house wraps help to reduce air infiltration and to protect
the insulation. Tyvek is not a vapor barrier or flashing material, however, and
given that the other principles are followed Tyvek is not strictly necessary.
Tyvek beneath the siding can help deflect water leakage and drainage away from
the insulation. In stick built houses where there is not so good a vapor barrier
Tyvek can lower the total amount of air infiltration, and hot air heat loss
through the house.

It isn't so much the particular way that materials or that certain designs are
used, rather that the basic principles are not compromised.

Good premises.

Ralph Hertle