The basics of a durable
and energy-saving house
Construction safety. The foundations carry the weight of
the house, protecting against the effects of uneven settlement of the ground,
which is a frequent reason for scratching and cracking walls. The durability and safety of the
structure ensures not only the construction of foundations in accordance with
the art of construction, but also the use of modern materials for bricklaying,
for example, foundation silicate, concrete or expanded clay concrete blocks.
Effective protection. The foundations should be protected
against chilling and wetness, wet ones quickly deteriorate as a result of
freezing of the water in them. It
also reduces their thermal insulation, and therefore the heat escapes faster
through the floor on the ground or ceiling above the basement and through the
walls of the ground. Moistened
foundations lead to the appearance of moisture in the walls of the ground
floor, peeling paint, and eventually the house grows fungi and mold. The new generation insulation, such as
extruded polystyrene boards, provides effective thermal protection. Moisture protection is ensured by
modern EPDM foils made of synthetic rubber, rubber-bituminous membranes,
bituminous and mineral masses, panels or membranes containing bentonite. Also for horizontal insulation, modern
pap - on fiberglass or polypropylene matrix is used.They have better properties,
are resistant to mechanical damage, low and high temperature and other
atmospheric conditions.
Comfort of workmanship. Contemporary materials for laying
foundation walls make work easier. It
is possible thanks to the appropriate dimensions of foundation blocks and their
better quality, which accelerates construction work. In the construction of some houses,
foundation slabs are made, which replace the traditional foundation footings.
WITH WHICH FOUNDATIONS
The materials from which
the foundations are made must be characterized by high durability and low water
absorption as well as resistance to frost, chemical and biological substances. At present, most foundations are made
of concrete and reinforced concrete. Foundation
walls can be built, among others from
concrete blocks or keramzyt blocks, but also silicate producers have special
foundation blocks in their offer. The
simplest in terms of construction and most commonly made in single-family
housing is the foundation bench with rectangular cross-section. It is a part of the building located
between the foundation wall and the ground. Its
dimensions depend on the bearing capacity of the ground and the size of the
load transferred by the object.On the benches, one, two or three-layer
foundation walls are made, which usually protrude 30-50 cm above the ground. The width of the walls is usually 25- 50 cm and depends primarily on the way of
their insulation and the design thickness and type of load-bearing walls.
In buildings with a
frame structure, where most loads are transmitted by poles, foundations are
built in the form of foundation footings. The
base of the foot is usually square, although it happens rectangular. Dimensions and reinforcement of the
feet depend on the load of the building and the load-bearing capacity of the
ground.
In the case of building
a house on land with low bearing capacity, a foundation in the form of a
foundation slab can be made.Then the house is placed on a reinforced concrete
slab lying almost on the surface of the supporting ground. It ensures even settlement of the
whole structure and distributes its loads to a large area.
WATERPROOFING
Types of isolation. The foundations use insulation:
- horizontal - protect
the walls against capillary rising of moisture, they are usually laid between
the bench and the foundation wall and at the interface of the foundation walls
and external walls of the building or in the basement walls above the ceiling;
- vertical - protect
against penetration of moisture from the ground, groundwater and rainwater; They are connected with horizontal
insulations and laid on the outside of the foundation and basement walls. A continuous and tight connection of
vertical and horizontal water insulation should be sought. This connection should provide a
barrier that will completely eliminate the possibility of groundwater entering
the walls, floors and the interior of the house.
Waterproofing materials. The following groups are
distinguished:
- liquid and plastic
bituminous materials - most of them should be used at temperatures above + 5 ° C . The
coating is laid on an even and cleaned substrate, otherwise the thickness of
the insulation may be less than required. In
the group of liquid and plastic bituminous materials are: asphalt emulsions
(used for priming concrete, sticking asphalt paper to foundation walls can also
be independent insulation, can be applied on damp substrates, dry up to a dozen
or so hours, do not dissolve styrofoam), asphalt solutions (laid The insulated
surface should be dry and clean.They can be used for gluing insulation from
roofing felt, priming the substrate for proper insulation and as a
self-insulating damp-proof or even anti-water insulation.They are inflammable
materials, dissolve polystyrene, dry about half a day), bituminous binders (
for cold or hot use, used both as self-contained light insulation and for
bonding roofing paper), bituminous masses (for waterproofing, using 3-5 layers
can act as waterproofing, part of bituminous mass is additionally reinforced
with fibers. and bituminous mixes
can also be reinforced with glass fabrics);
- watertight mortars -
cement mortars modified with synthetic resins;
- bentonite materials -
mineral-based bentonite, which can absorb a large amount of water and forms a
layer of insoluble gel.These materials are in the form of panels and membranes;
- roofing felt - the
most commonly used waterproofing material. Papa
consists of several layers - the middle is a matrix of polyester nonwoven or a
veil of glass fibers. It is
covered on both sides with asphalt, which can be modified with polymers, which
significantly increases the flexibility of the roofing felt. From the bottom it is mostly a foil. Insulation papers are marked with
symbols, eg I 400/1600 means that the weight of the roofing paper is 400 g / m² and that it is
coated with asphalt in an amount of 1,600
g per 1 m² . Papers are suitable for both
anti-moisture (light) and anti-water (heavy) insulations. Modified papers are laid on walls with
a clean, smooth and primed surface, at a temperature of -5 ° C ;
- waterproofing foils -
used for vertical and horizontal insulation. In
this group there are, among others vapor-tight
films - used both as damp and anti-water insulations. Depending on the type of insulation,
only a different thickness of the film is selected and other joining methods
are used. When waterproofing
foundations, do not use foils thinner than 0.2
mm . Thicker foils provide greater
stiffness and resistance to mechanical damage caused, for example, when
backfilling the ground. Foils can
also be self-adhesive or weldable (combined with a heater) and pressed, or
bucket (made of high-density polyethylene, can be attached to the wall
mechanically with nails, pressed into mortar or self-adhesive). The bucket foil is laid out with
embosses towards the wall, which causes a gap between the wall and the wall to
allow moisture to escape from the wall. Bucket
films are used as a protective layer for thermal and waterproofing. Modern bucket films have special locks
to facilitate assembly and improve the tightness of the insulation.
Foundation protection
DRAINAGE
It is a network of
installations arranged around the building, which collects water accumulating
around the foundations and drains it to a safe distance from the house. Drainage is necessary if there are
impermeable layers in the substrate and when the groundwater is low. External lath drainage of a
single-family home should be designed when the ground layer layout or the level
of groundwater table will cause permanent or periodic contact of foundation
walls and foundations with water.
PATH OF ENERGY SAVING
The foundations must be
warm
Only foundation walls
made of a heat-proof material, i.e. solid blocks of expanded clay, do not
require an additional layer of insulation. all
other needs to be warmed up.
In most cases, the
foundations are warming from the outside. Thermal
insulation is also placed in the layered foundation wall - between the
supporting and the covering layer. Only
in the case of single-layer walls, the underlay is allowed to lay the
insulation from the inner sides of the foundation walls.
Foundation walls should
be insulated at least 1 m below ground level. In practice, they are warmed up to the
level of footings, similar to basement walls. The
following are used most often to insulate foundations:
# styrofoam boards with
increased resistance to compression;
#boards ribbed or
grooved laminated with geotextile. Ryfl
e will help to remove excess moisture from the external wall of the building;
# harder extruded
polystyrene (XPS) boards with a thermal conductivity coefficient λ more favorable than styrofoam(approximately 0.027 W / (m · K)) and much
less water absorption. XPS boards
can also be grooved with a layer of geotextile that protects the grooves from
clogging;
# hard PIR polyurethane
foam boards - characterized by high thermal insulation as well as resistance to
mechanical damage;
# expanded clay
aggregate used as backfilling of foundation excavations and specially designed
for this purpose hydrophobized stone wool slabs.
