Performing plastering works in the winter § 42. General information preparation and drying of rooms and surfaces

General information . In winter, plastering works are performed in compliance with a number of additional requirements.

The moisture content of brick or stone walls to be plastering should not exceed 8%. The degree of humidity is determined by laboratory. Those building structures (window and door slopes, niches) that are subjected to rapid cooling should be finished before the onset of cold weather. If they are trimmed after the onset of cold weather, then take measures to protect the plaster from premature freezing: plaster is warmed, heated.

Preparation, storage, transportation of plaster solutions should be organized in such a way that the solution delivered to the work site, at the time of its application, has a temperature not lower than + 8 ° C. This can be achieved when the room, bunker, solution pipelines are warmed and the temperature in the room is not lower than + 10 ° С. Mortar pipes located in the open air or in unheated premises should be insulated.

The execution of exterior plastering at air temperatures below -5 ° C is allowed with solutions containing chemical additives, which give the solutions the ability to harden in the cold and achieve the required strength. It is also allowed to plaster with solutions with ground quicklime.

Stone and brick walls, folded by the method of freezing, are allowed to plaster, when from the side of the plastering layer the masonry has thawed to a depth of at least half the wall thickness. . The use of hot water to accelerate the heating of frozen walls or to remove ice from them is not allowed.

Preparation The building as a whole, or its premises to be plastered, is prepared in advance. First of all, they pierce the gaps between the walls, door and window frames and plaster the blind spots and window slopes. Inserted window covers glaze. Doors tightly closed. Attic and interfloor floors are insulated.

According to the specifications plastering work is allowed to be performed in

winter time with a stable average indoor temperature near the exterior walls at a height of 0.5 m from the floor level is not lower than + 8 ° С. To accelerate the drying of the plaster, it is recommended to bring the temperature to + 10-16 ° С. At the same time, the temperature at the ceiling should be no higher than + 30 ° C. At higher temperatures, the plaster dries quickly, becomes cracked, and loses strength.

In rooms where the temperature is below + 8 ° C, it is forbidden to work, because the plaster dries for a long time and, moreover, deposited on the frozen walls, in the spring it can flake off, as the walls thaw, release moisture and it breaks the adhesion of the plaster to the wall. Under these conditions, wooden, fiberwood, reed and straw Solomite surfaces are highly saturated with moisture, swell and increase in volume. When dry, they warp and tear the plaster.

Before plastering from surfaces it is necessary to remove the frost and then warm the room well.

Heating and drying . Plasters on different binders are dried differently. For example, a normal amount of carbon dioxide is required for the normal process of drying and curing lime plasters. Drying lime plasters in an accelerated way does not give good results: the plaster turns out to be fragile and cracks heavily. Lime and lime-gypsum plaster is dried on average 10-15 days, airing the room two or three times per hour. Cement and cement-lime plasters are dried for 6-7 days without airing the premises, because moist air is required during the hardening period. When drying plaster from a complex solution, it is necessary to focus on the main binder.

Frozen wet plaster should be immediately heated, removed peeling places, fix them and then dry.

The best heating when drying plaster is central. If there is no central or stove heating, arrange a temporary.

For large volumes of plastering work air heaters are used. These installations dry the plaster for 6-8 days at an air temperature of + 30 ° C. As soon as the plaster dries to the required humidity (8%), the drying is stopped and the temperature in the room is kept at + 8 ° C so that the walls do not cool down and wet stains do not appear on them.

For drying large plastered surfaces, air heaters are also used. The unit includes a heater with a firebox, a blower unit with a centrifugal fan forcing hot gases through air ducts (pipes), a set of pipes and an additional fan forcing air. Air ducts pass into the building through window or door openings. If there are workers in the room, then only hot air is supplied to the building, and exhaust carbonic gases are taken outside.

The electric air heater has a cylindrical casing of sheet steel, in which heating elements are placed on pedestals. In the electric heater fan blows air from the electric motor, where it heats up and flows outside.

Heat generator TG-150 is designed for use in areas with air temperature from -35 ° C. It runs on liquid fuel.

The infrared burner is designed to dry the plaster in buildings under construction and repair, subject to air exchange at least two times per hour, ensuring timely removal of combustion products.