INDUSTRY SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 02, 2016 USD ($)	Oct. 03, 2015 USD ($)	Jul. 04, 2015 USD ($)	Apr. 04, 2015 USD ($)	Jan. 03, 2015 USD ($)	Sep. 27, 2014 USD ($)	Jun. 28, 2014 USD ($)	Mar. 29, 2014 USD ($)	Jan. 02, 2016 USD ($) item	Jan. 03, 2015 USD ($)
INDUSTRY SEGMENT INFORMATION
Number of industry groups in which the entity operates | item									2
Revenues from external customers	$ 35,120	$ 36,165	$ 34,865	$ 30,685	$ 33,319	$ 34,366	$ 37,367	$ 26,824	$ 136,835	$ 131,876
Depreciation, depletion and amortization	484	$ 640	$ 651	$ 646	546	$ 764	$ 743	$ 738	2,421	2,791
Operating (loss) income									2,516	(8,591)
Segment assets	75,755				71,801				75,755	71,801
Capital expenditures									2,303	2,607
Concrete Aggregates and Construction Supplies [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers									55,319	55,732
Depreciation, depletion and amortization									1,364	1,768
Operating (loss) income									(256)	(8,863)
Segment assets	31,791				30,800				31,791	30,800
Capital expenditures									1,539	1,389
Doors [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers									16,981	16,213
Depreciation, depletion and amortization									128	124
Operating (loss) income									1,280	1,159
Segment assets	6,471				6,518				6,471	6,518
Capital expenditures									31	91
Heating and Cooling [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers									39,498	34,286
Depreciation, depletion and amortization									504	462
Operating (loss) income									3,371	1,109
Segment assets	22,628				17,762				22,628	17,762
Capital expenditures									494	184
Evaporative Cooling [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers									25,022	25,630
Depreciation, depletion and amortization									399	386
Operating (loss) income									1,135	1,269
Segment assets	12,730				13,290				12,730	13,290
Capital expenditures									239	940
Corporate, Non-Segment [Member]
INDUSTRY SEGMENT INFORMATION
Revenues from external customers									15	15
Depreciation, depletion and amortization									26	51
Operating (loss) income									(3,014)	(3,265)
Segment assets	2,135				3,431				$ 2,135	3,431
Capital expenditures										3
Construction Products [Member]
INDUSTRY SEGMENT INFORMATION
Number of reportable segments | item									2
Revenues from external customers									$ 72,300	71,945
Depreciation, depletion and amortization									1,492	1,892
Operating (loss) income									1,024	(7,704)
Segment assets	38,262				37,318				38,262	37,318
Capital expenditures									$ 1,570	1,480
Heating Ventilation and Air Conditioning Products [Member]
INDUSTRY SEGMENT INFORMATION
Number of reportable segments | item									2
Revenues from external customers									$ 64,520	59,916
Depreciation, depletion and amortization									903	848
Operating (loss) income									4,506	2,378
Segment assets	$ 35,358				$ 31,052				35,358	31,052
Capital expenditures									$ 733	$ 1,124