The Ontario Building Code | Concrete Mixes

9.3.1.7. Concrete Mixes

(1) For site-batched concrete, the concrete mixes described in Table 9.3.1.7. shall be considered acceptable if the ratio of water to cementing materials does not exceed,

(a) 0.45 for garage floors, carport floors and all exterior flatwork,

(b) 0.65 for interior floors other than those for garages and carports, and

(c) 0.70 for all other applications.

(2) The size of aggregate in unreinforced concrete mixes referred to in Sentence (1) shall not exceed,

(a) 1/5 the distance between the sides of vertical forms, or

(b) 1/3 the thickness of flatwork.

Table 9.3.1.7.
Concrete Mixes

Forming Part of Sentence 9.3.1.7.(1)

Item	Column 1	Column 2	Column 3	Column 4	Column 5	Column 6	Column 7
	Maximum Size of Coarse Aggregate, mm	Materials, volume
		cement		Fine Aggregate (damp average coarse sand)		Coarse Aggregate (gravel or crushed stone)
		Parts	L(1)	Parts	L	Parts	L
1.	14	1	28	1.75	49	2	56
2.	20	1	28	1.75	49	2.5	70
3.	28	1	28	2	56	3	84
4.	40	1	28	2	56	3.5	98

Notes to Table 9.3.1.7.:

⁽¹⁾ A 40 kg bag of cement contains 28 L.