Hardwood floor in.
													
																	Draw straight line on the floor. 
									
	
		
	
																	Pull the line very taut and the hold the line down on the mark with one hand. 
																	Use a bubble level as you go to make sure the lines you re drawing are perfectly straight. 
																	If the bubble goes to the center of the level between the 2 black lines your line is straight. 
																	Hi all i have to draw a straight line on a floor before i put tiles. 
															
													
									
	
		
	
																	Snap the chalk line leaving a straight chalk mark on the subfloor. 
																	Place the level along the line. 
																	A chalk line can be as long as needed being. 
																	This video is about how to make a first straight lane during hardwood floor installation on concrete. 
															
													
									
	
		
	
																	When any project calls for drawing a long straight line on a floor wall or similar flat surface a professional mechanic will use a chalk line. 
																	The problem is that the width at one end of the room is 290 cm while at the other end of the room is 295 cm so i assume that the walls are not straight.