Wooden window profiles should be made in a way that ensures water drainage. What minimum angle of inclination is required here?
The minimum angle of inclination of the window profiles is 15 °, an angle of 30 ° is preferred.

To ensure a sufficiently thick layer of coating on the edges of window profiles, all edges should be rounded. What should be the minimum radius of rounding? The edges must be rounded with a radius of min. 2 mm.

In which group of strength requirements the glued window profiles must be made, if it is planned to paint them with transparent or opaque dark varnishes? Gluing the profiles must comply with the B4 group of strength requirements, i.e. the highest.

The glazing of the windows should correspond to the group of strength requirements B3, if they are to be painted with transparent varnishes or dark opaque varnishes. How to recognize, does the glazing correspond to the B3 strength group?
With glazing made in the B3 strength group, on the outside, an elastic layer of varnish is made on the putty layer.

Please list the unacceptable wood defects in the window elements, which are to be coated with transparent varnish. In wood intended for window elements, which are to be coated with clear varnish, the following disadvantages are unacceptable:
1) wood-destroying fungi, few incipient blue stains are allowed, color changes will not be visible after coating;
2) insect larval corridors – wood pests, the presence of single pavements is allowed - diameter up to 2 mm;
3) scratches and cracks, especially cross scratches;
4) visible edgings;

5) traces of pita and plane;
6) presence of white in deciduous wood;
7) knots – diameter greater than 5 mm;
8) pinned knots on the outside – diameter above 25 ram, kittens that are not glued in on the entire surface, kittens in rows;
9) twisting of the fibers and deviation of the fibers above 2 cm/m.

In the wood of the old scarf, round orifice holes in diameter are visible 1-2 mm. What pests feed here?
The size of the outlet openings indicates a household door knocker (Anobium pierced), it can also be a pulpitis (Linear light). Larval galleries should be discovered for reliable diagnosis. The feeding pavements of the house door knocker are irregular, while the pulpwood is arranged mainly in the direction of the wood grain. Determining the moisture content of the wood can also aid in identification. Domestic door knocker attacks especially strongly damp wood, at low temperature.

How you can recognize the wood attacked by the common drain?
The drain holes are sized 5-10 mm and oval cross-section. Generations of let off fly out at intervals of several years.

For a reliable diagnosis, a wood examination can be made, consisting in:
– tapping (thud);
~ listening to the murmur of feeding insects (preferably using a hearing aid);
– exposure of larval galleries (by chipping off corners).

(The larval galleries are just below the surface and are filled with light wood flour).