The main frame of the roundhouse would have been made of upright timbers, which were interwoven with coppiced wood - usually hazel, oak, ash or pollarded willow - to make wattle walls. This was then covered with a daub made from clay, soil, straw and animal manure that would weatherproof the house. The roof was constructed from large timbers and densely thatched. All of the domestic life would have occurred within the roundhouse.
Castell Henllys. "The Iron Age Celts' clothes might have looked like the tartan you see in Scotland and Ireland today, with checks and stripes. The Celts used berries and plants to dye the wool different colours."-BBC
A new pair of publications from the Latvian National Culture Centre: a 2017 wall calendar and a planner with photos of authentic replicas of 7th-14th century garb representing all the chiefdoms of Late Iron Age Latvia. This one is Latgallian (not sure of the century). I'm going to try to get some of these for balticsmith.com.
The La Tène culture was a European Iron Age culture named after the archaeological site of La Tène on the north side of Neuenburgersee in Switzerland, where a rich cache of artifacts was discovered by Hansli Kopp in 1857. La Tène culture developed and flourished during the late Iron Age (from 450 BCE to the Roman conquest in the 1st century BCE) in Belgium, eastern France, Switzerland, Austria, Southern Germany, the Czech Republic, Poland, Slovakia, Slovenia, Hungary and Romania.