Signal loss through roof for 10, 2 meter and 70cm (db) ?

[LB5KE]

Does any one have a tabell for the signal loss for a roof with bricks vs various frequencies?

[KG4RUL]

Jorn, I assume by "brick" you mean a tile roof?  Given the variations is supporting structures, thickness and mineral content in the clay, etc . in the roof tiles, you would most likely have to do in situ testing to come up with any viable data.  And, it would only apply to that particular roof installation.  So, in a nut shell, there is no table that I have ever encountered.

[LB5KE]

Yes i meant tile roof. However other materials wood be interesting. 

[WB6BYU]

I don't have specific data, but if the roof tiles are not glazed the losses probably will be
much higher when the tiles are wet.

[AA4HA]

Ye Gods! That is a complicated question. Going "through" something is going to have greater attenuation at higher frequencies (other than a few very unique frequencies and materials).

I have enough problems just trying to figure out the "reflectivity" of building materials for non-line-of-sight 3.65 GHz Wi-Max systems. Surface finish, moisture content, minerals, etc...

You are going to have materials (wood, fiberboard) that may only cost you a few dB. Masonry may have a nearly perfect ability to absorb RF energy, making it a very good shielding material except at very low frequencies (<HF).

Any answer you come up with is probably going to need to be derived empirically by field testing on your part. The challenge will be in controlling the test environment to minimize reflectivity that would make it appear that the signal "goes through" something.

[KQ6Q]

The simplest solution - take a receiver or HT that covers the frequencies you're interested in up into the attic, tune to known broadcast or aviation or public service stations  or repeaters, and see what you can hear, compared to what you can hear with the same radio outdoors in the same neighborhood. AA4HA mentioned 'empirical testing' - I've just given you an expanded explanation of that....

[LB5KE]

OK, i have done some tests with the help of a fellow ham at 70cm. The best result i got from the attic is around -6db compared with having the antenna (1 S-grade) outside. I manage to the get that by placing the antenna close to the wooden part at the end of the attic. However at average the damping was higher around 12db. Placing the antenna outside is a must @ 70cm. The good thing is that a 70cm antenna doesn't take up much space it shouldn't be to hard to hide.

[KB1BZR]

Wood ?? What is the loss going through wood ? Trees ??