WINDOWS, DOORS AND BEAMS
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WINDOWS, DOORS, BEAMS AND ARCHES
For door and window lintels use channel blocks. Beams are made the same way. For
spans over 205 cm, use two or more layers. For very heavy loads use 2 rows of blocks side
by side in layers. Usually smooth 9-mm-diameter rebar is sufficient.
WINDOWS AND DOORS
For a 2-layer channel block
lintel extend the steel rebar
1 block lengths beyond
the opening.
A two-layer reinforced-concrete lintel.
Ordering Wooden Door and Window
Frames
Order (or make) door and window frames
after laying the blocks. In this way you will
avoid having a gap around the frame or a
frame that won’t fit in the window opening.
If the frame is installed before all the blocks
are laid, there will be a gap or, the top of
the frame will not fit even with the row of
blocks on top of it.
A one-layer reinforced-concrete lintel.
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WINDOWS, DOORS AND BEAMS
Keeping Water Out
Fastening Door and Window Frames
Use galvanized steel flashing above and a
fired brick sill below to keep rain from coming
into a window.
There are many ways to fasten a window
frame to the blocks. One way is to:
1. Drill holes in the blocks.
2. Put plastic or wood inserts in the holes.
3. Screw screws through the frame and into
the insert.
Avoid putting holes in the bottom of the
window frame: they can cause leaks.
Window head, sill and frame
A boy on a bench (a beam), Udon Thani, Thailand
WINDOWS, DOORS AND BEAMS
21
Independent Breast Windows
Independent Breast windows are one way to prevent cracking at window corners due to
settling. The breast (the area directly under the window) is independent of the rest of the
wall. This also allows the window to be converted to a door.
A wall being built with an independent breast window: Songkla, Thailand.
BEAMS
Villagers’ handicrafts store, Pakse, Laos
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WINDOWS, DOORS AND BEAMS
ARCHES
Since ancient times, unreinforced arches (no
steel rebar) have been used for door and
window openings. They are beautiful,
peaceful to the eye, and they distribute the
weight of the building naturally around an
opening. They are strong and durable. Here
you will see 3 arch designs with some
building methods. It is best to draw an arch
carefully before trying to build it.
Arches add beauty and strength to a building.
A 205-cm Semi-Circle Arch
A 90-cm semicircle arch made with Rhino blocks.
Notice the special keystone at the top of the arch:
it is needed to fill the odd-sized opening at the top.
WINDOWS, DOORS AND BEAMS
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Arch Construction
Laying an arch is not so hard, but it does
require planning and attention to details.
Prepare blocks by filling in their holes. Cast
keystones or cut springpoint blocks. Make
an arch framework. Put it in place. Mortar
the blocks up around the framework.
Steel frameworks for arch building.
Two keystones and their molds. They are concrete
with soil dust mixed in so they will be the same color
as the earth blocks.
A 205-cm steel framework being used to build an
arch. Mortar the blocks in place with mortar
colored with soil dust.
The blocks in an arch must be solid: fill in the holes
in the blocks with mixed cement mortar. Cast the
mortar in the holes in advance so it is hard before
laying the blocks.
Blocks next to an arch need to be cut to fit
around it. Lay the blocks next to and
above the arch immediately and remove
the steel framework within 2 days. The arch
will settle a little under the load of the
blocks. If you wait until the mortar between
the arch blocks is hard then the arch will
crack when it settles. If you load it soon
after building it, the mortar will give and
settle too.
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WINDOWS, DOORS AND BEAMS
90-cm Independent-breast “Dutch” Arch
The following illustrations show how to build up a “Dutch” arch. The arch springpoint
blocks are specially cut, but this arch requires no special keystone. It will fit exactly in 3
courses of blocks. The sides of the openings are buttresses for the walls.
5
Specially cut
springpoint
blocks
1
2
3
4
6
7
Construction of a 90-cm independent breast window with a Dutch arch.