Exhibit 11

Simpson Manufacturing Co., Inc. and Subsidiaries
Computation of Earnings Per Common Share

(Unaudited)

Basic Earnings per Share

	Three Months Ended September 30,				Nine Months Ended September 30,
	2004		2003		2004		2003
Weighted average number of common shares outstanding	47,643,694		49,355,296		48,115,666		49,242,808
Net income	$	24,184,042	$	18,557,490	$	63,948,009	$	47,263,999
Basic net income per share	$	0.51	$	0.38	$	1.33	$	0.96

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Diluted Earnings per Share

	Three Months Ended September 30,				Nine Months Ended September 30,
	2004		2003		2004		2003
Weighted average number of common shares outstanding	47,643,694		49,355,296		48,115,666		49,242,808
Shares issuable pursuant to employee stock option plans, less shares assumed repurchased at the average fair value during the period	846,992		878,908		824,798		773,976
Shares issuable pursuant to the independent director stock option plan, less shares assumed repurchased at the average fair value during the period	14,410		12,970		13,144		11,190
Number of shares for computation of diluted net income per share	48,505,096		50,247,174		48,953,608		50,027,974
Net income	$	24,184,042	$	18,557,490	$	63,948,009	$	47,263,999
Diluted net income per share	$	0.50	$	0.37	$	1.31	$	0.94

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