Document and Entity Information	3 Months Ended
	Mar. 31, 2013	May 06, 2013 Class A Common Stock	May 06, 2013 Class B Common Stock
Entity Registrant Name	WATTS WATER TECHNOLOGIES INC
Entity Central Index Key	0000795403
Document Type	10-Q
Document Period End Date	Mar. 31, 2013
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		28,762,203	6,588,680
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q1