4k2ml32343m3
2019-01-16 12:49:11
- #1
Hello,
my house, currently in the shell construction phase, received a pine purlin roof truss. The roof is not yet covered, but the roofing membrane is on.
Upon inspection, I noticed that the rafters and collar beam layer are affected by blue stain. Some rafters, in my opinion, show a high infestation of larval feeding tunnels. The construction company is being uncooperative. According to DIN 4074-1, feeding tunnels up to 2mm in diameter are permissible. It has been proven that the holes are oval, 5mm wide and just under 2mm high. The construction company said that I measured incorrectly. The measurement must be taken across, as if it were a circle. Therefore, the DIN would be complied with. Furthermore, it is pointed out that a note in the DIN states that feeding tunnels up to 5 mm in diameter do not affect the wood strength. This is indeed mentioned, but not in the table with the sorting by cut (S10 not visible).
Furthermore, I found a larva in the wood. It is still relatively fresh, definitely not grilled after kiln drying.
A wood protection expert suspects house longhorn beetle, i.e. dry wood insect. The construction company claims it is a fresh wood insect, flat-faced longhorn beetle, but since the wood was dried, there is no danger.
Do you have any tips? Especially regarding the measurement method of the 2mm. The invoice for the roof truss has not yet been paid.
my house, currently in the shell construction phase, received a pine purlin roof truss. The roof is not yet covered, but the roofing membrane is on.
Upon inspection, I noticed that the rafters and collar beam layer are affected by blue stain. Some rafters, in my opinion, show a high infestation of larval feeding tunnels. The construction company is being uncooperative. According to DIN 4074-1, feeding tunnels up to 2mm in diameter are permissible. It has been proven that the holes are oval, 5mm wide and just under 2mm high. The construction company said that I measured incorrectly. The measurement must be taken across, as if it were a circle. Therefore, the DIN would be complied with. Furthermore, it is pointed out that a note in the DIN states that feeding tunnels up to 5 mm in diameter do not affect the wood strength. This is indeed mentioned, but not in the table with the sorting by cut (S10 not visible).
Furthermore, I found a larva in the wood. It is still relatively fresh, definitely not grilled after kiln drying.
A wood protection expert suspects house longhorn beetle, i.e. dry wood insect. The construction company claims it is a fresh wood insect, flat-faced longhorn beetle, but since the wood was dried, there is no danger.
Do you have any tips? Especially regarding the measurement method of the 2mm. The invoice for the roof truss has not yet been paid.