INDUSTRY SEGMENT INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 04, 2015	Mar. 29, 2014	Jan. 03, 2015
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	$ 30,685us-gaap_SalesRevenueGoodsNet	$ 26,824us-gaap_SalesRevenueGoodsNet
Depreciation, depletion and amortization	646	738
Operating Income (Loss)	(219)us-gaap_OperatingIncomeLoss	(1,685)us-gaap_OperatingIncomeLoss
Segment assets	72,762us-gaap_Assets	71,801us-gaap_Assets	71,801us-gaap_Assets
Capital expenditures	93	807
Concrete Aggregates and Construction Supplies [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	10,565	10,318
Depreciation, depletion and amortization	337	456
Operating Income (Loss)	(728)	(1,583)
Segment assets	31,098	30,800
Capital expenditures		623
Doors [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	4,188	3,896
Depreciation, depletion and amortization	31	36
Operating Income (Loss)	338	395
Segment assets	6,757	6,518
Capital expenditures	1	34
Heating and Cooling [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	9,146	6,924
Depreciation, depletion and amortization	142	129
Operating Income (Loss)	497	(30)
Segment assets	16,261	17,762
Capital expenditures	59	56
Evaporative Cooling [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	6,782	5,683
Depreciation, depletion and amortization	123	105
Operating Income (Loss)	451	263
Segment assets	15,959	13,290
Capital expenditures	33	94
Corporate, Non-Segment [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	4	3
Depreciation, depletion and amortization	13	12
Operating Income (Loss)	(777)	(730)
Segment assets	2,687	3,431
Construction Products [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	14,753	14,214
Depreciation, depletion and amortization	368	492
Operating Income (Loss)	(390)	(1,188)
Segment assets	37,855	37,318
Capital expenditures	1	657
Heating Ventilation and Air Conditioning Products [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers	15,928	12,607
Depreciation, depletion and amortization	265	234
Operating Income (Loss)	948	233
Segment assets	32,220	31,052
Capital expenditures	$ 92	$ 150

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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