Asturian techu, Portuguese teto, Galician teito, French toit, Italian tetto
Old Irish tech "house," Old Welsh tig 'id.,' Old Breton bou-tig "stable," Old Cornish ti "house"
Old Norse þak "roof," Old High German dach 'id.,' Old English þæc 'id.'
Old Prussian stogis "roof," Lithuanian stógas 'id.,' Latvian stâgs 'id.'
Ancient Greek τέγος (tégos) "roof"
"[In Indo-European society] roofs were thatched; words for 'roof' in some IE languages are cognate with words for 'thatch' in others, all of them derived from a verbal root meaning 'to cover.'" ~ B. Fortson, Indo-European Language and Culture (2011)