Author: Bill Crouse From http://www.christianinformation.org/article.asp?artID=71

I.  Introduction  
 
   A.  Biblical Passages:  Gen. 6-8; Matt. 24:37,38; Lk. 17:26,27;  
    I Pet.  3:20;II Pet. 2:5.  
 
   B.  The story of Noah and his family being spared from a world-  
       wide deluge (a judgement by God) is one of the most  
       important in the Old Testament.  Much is learned about the  
       nature of God from this story.  For example:  It shows  
       He is a holy God and cannot tolerate sin.  It shows He  
       is a just God and that sin will not go unpunished.  It  
       shows He is a God of mercy in that He spares some.   It  
       shows God's power in that the Flood unleased great power

A.  The Designer was God Himself.  We do not need to assume  
        Noah knew anything about ship-building.  The instructions  
        for design are given in Gen. 6:14ff.  
 
    B.  Construction Materials  
 
        The Bible says the Ark was to be built of "gopher wood".  
        "Gopher" is the actual Hebrew word.  In early English  
        translations the meaning of the word was unknown so it was  
        left untranslated.  The NIV translates it "cypress wood";  
        however, this is only a guess.  It was undoubtedly  
        translated this way due to the fact that cypress wood is  
        highly resistant to rot.  What this material was is still  
        a mystery.  It could have been a pre-flood wood with which  
        we are not familiar.  
 
        It is almost certain that Noah did not construct a  
        standard wooden ship of the kind we are familiar.  
        According to nautical engineers the longest wooden vessel  
        ever built was 360 feet in length and was not seaworthy.  
        Because of the wave action of the sea only wooden ships  
        shorter than this will be seaworthy.  Therefore, we must  
        conclude that Noah used some other method of construction  
        to overcome this problem.

1.  The Biblical word for Ark is "tebah".  It is used 28  
            times in the OT and is only used of Noah's Ark and for  
            the container in which Moses was hidden among the  
            bulrushes.  Because of a similar Egyptian word meaning  
            "box", and the ultimate purpose of the Ark, we believe  
            the Ark was not like a streamlined vessel designed to  
            easily glide through the water.  More likely it was  
            shaped like a rectangular barge which floated rather  
            low in the water.  From the story in the Bible, it  
            also would appear that Noah had no control over the  
            vessel.  He, and it contents were at the total mercy  
            of God.  
 
        2.  The Ark had three stories with only one door.  The  
            phrase in Gen. 6:16, "Make a roof for it and finish  
            the Ark to within 18 inches of the top." is  
            problematic in that the words used are obscure.  Most  
            commentators believe it means leave an 18 inch space  
            at the top that is open all around the vessel.  This  
            then would be for ventilation, and when water entered  
            it would drain out somewhere below, similar to the  
            vents in cars.  
 
        3.  The Ark was to be coated inside and out with pitch.  
            Again the Hebrew word for "pitch" is obscure.  It was  
            more likely some resinous material used not only to  
            waterproof the vessel but also to prevent decay.  If  
            Noah was 480 years old when God told him to build an  
            Ark and 600 when the Flood came, it is reasonable to  
            assume that the construction of the Ark took place  
            during this 120 year period (See Gen. 6:3 along with  
            I Pet. 3:20).  The need for this preservative was  
            essential.  It is also possible that things did not  
            decay as rapidly in the pre-flood atmosphere.  
 
        4.  The phrase in the NIV (6:14) "make rooms" is also  
            problematic in that the word is obscure.  The Hebrew  
            is "qnm".  Since Hebrew did not have any vowels when  
            it was written, scholars speculate that the word could  
            be either "qinnim" or "qanim".  The former would mean  
            either "rooms" or "nest", and the later, "reeds".  
            Most english translations translate as in the former.  
            However, some of the better and more recent  
            commentaries, believe it should be translated "reeds"  
            since the context is building materials.  If in  
            reality it is "reeds", then somehow reeds were part  
            of the construction material.  Large boats are still  
            made from reeds and are very seaworthy.  The Egyptians  
            still use reeds for caulking their wooden ships.

(When considering its size it obviously was not the backyard  
     effort of a primitive river-dweller!)  
 
     A.  It is given in cubits as being 300 cubits long by 50  
         cubits wide and 30 cubits high.  A cubit in the OT was  
         generally about 17.5 inches.   However, an Egyptian royal  
         cubit measured about 20.5 inches.  Since Moses was  
         educated in Egypt we must allow for the possibility that  
         the longer measurement was meant here.  The Ark,  
         therefore, could have measured from 437 feet to 512 feet  
         in length!  It was not until the late 19th century that  
         a ship anywhere near this size was built.  
 
     B.  It's Ratio  
 
         The Ark had a ratio (length x width x height) of 30 x 5  
         x 3.  According to ship-builders, this ratio represents  
         an advanced knowledge of ship-building since it is the  
         optimum design for stability in rough seas.  The Ark, as  
         designed by God, was virtually impossible to capsize!  
         It would have to have been tilted over 90 degrees in  
         order to capsize.  
 
     C.  Its Volume.    
 
         With the shorter cubit the Ark would have an internal  
         volume of 1,518,750 cubic feet, or the equivalent of 569  
         standard railroad boxcars.  If the average sized animal  
         was the size of a sheep it means the Ark could hold over  
         125,000 sheep.  (Assuming the shape of the Ark to be  
         rectangular there would have been over 100,000 sq. ft of  
         floor space!)

Though the Bible does not say, it seems reasonable that Noah  
    employed a large group of workman to build the Ark.  If Noah  
    started building the Ark soon after God spoke to him, then the  
    process of building the Ark may have taken close to 120 years.